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From jbap...@apache.org
Subject [32/51] [partial] incubator-impala git commit: IMPALA-3398: Add docs to main Impala branch.
Date Thu, 17 Nov 2016 23:12:10 GMT
http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3be0f122/docs/topics/impala_errata.xml
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diff --git a/docs/topics/impala_errata.xml b/docs/topics/impala_errata.xml
new file mode 100644
index 0000000..c7ad9c0
--- /dev/null
+++ b/docs/topics/impala_errata.xml
@@ -0,0 +1,1378 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
+<concept id="errata">
+  <title>Impala Documentation Errata</title>
+  <titlealts audience="PDF"><navtitle>Doc Errata</navtitle></titlealts>
+  <prolog>
+    <metadata>
+      <data name="Category" value="Impala"/>
+      <data name="Category" value="Release Notes" />
+      <data name="Category" value="New Features" />
+      <data name="Category" value="What's New" />
+      <data name="Category" value="Fixed Issues" />
+      <data name="Category" value="Incompatible Changes" />
+    </metadata>
+  </prolog>
+
+  <conbody>
+
+    <p>
+      This page shows changes in the Impala documentation.
+      These different views are experiments to see what kind(s) of
+      representation are most helpful.
+      Some changes are tied to a release.
+      Other improvements are the result of a particular JIRA issue and have
+      been backported to multiple releases where appropriate.
+    </p>
+
+    <p outputclass="toc inpage"/>
+  </conbody>
+
+    <concept id="by_release">
+      <title>Changes by Release</title>
+      <conbody>
+        <p>
+          This section shows recent releases of CDH and corresponding Impala releases,
+          and the documentation pages that have substantial changes for each release.
+        </p>
+        <p outputclass="toc inpage"/>
+      </conbody>
+
+      <concept id="release_2_6_0">
+        <title>CDH 5.8 / Impala 2.6.0</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_6_0" href="impala_alter_table.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_breakpad.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_create_database.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_create_table.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_complex_types.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_drop_database.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_drop_table.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_perf_stats.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_insert.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_reserved_words.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_load_data.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_parquet_annotate_strings_utf8.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_parquet_fallback_schema_resolution.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_runtime_bloom_filter_size.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_runtime_filter_max_size.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_runtime_filter_min_size.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_runtime_filter_mode.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_runtime_filtering.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_s3_skip_insert_staging.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_select.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_s3.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_txtfile.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_avro.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_parquet.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_rcfile.xml"/></li>
+         <li><xref outputclass="release_2_6_0" href="impala_seqfile.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+
+      <concept id="release_2_5_0">
+        <title>CDH 5.7 / Impala 2.5.0</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_5_0" href="impala_admission.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_count.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_create_database.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_create_function.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_create_table.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_describe.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_disable_row_runtime_filtering.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_disable_streaming_preaggregations.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_drop_function.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_datetime_functions.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_misc_functions.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_reserved_words.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_string_functions.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_udf.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_joins.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_load_data.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_max.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_max_num_runtime_filters.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_min.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_optimize_partition_key_scans.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_partitioning.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_runtime_bloom_filter_size.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_runtime_filter_max_size.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_runtime_filter_min_size.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_runtime_filter_mode.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_runtime_filter_wait_time_ms.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_shell_running_commands.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_runtime_filtering.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_scan_node_codegen_threshold.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_schedule_random_replica.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_set.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_show.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_operators.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_scalability.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_processes.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_truncate_table.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_perf_hdfs_caching.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_impala_shell.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_parquet.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_shell_commands.xml"/></li>
+         <li><xref outputclass="release_2_5_0" href="impala_shell_options.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+
+      <concept id="release_2_3_0">
+        <title>CDH 5.5 / Impala 2.3.0</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_3_0" href="impala_alter_table.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_array.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_avg.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_compute_stats.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_count.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_create_database.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_create_function.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_create_table.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_create_view.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_complex_types.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_jdbc.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_odbc.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_ssl.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_describe.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_drop_database.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_drop_table.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_exec_single_node_rows_threshold.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_authorization.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_grant.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_group_by.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_insert.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_bit_functions.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_datetime_functions.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_math_functions.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_reserved_words.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_string_functions.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_conversion_functions.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_udf.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_joins.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_live_progress.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_live_summary.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_load_data.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_map.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_max.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_min.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_ndv.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_order_by.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_aliases.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_tables.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_views.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_partitioning.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_refresh.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_revoke.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_select.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_set.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_operators.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_struct.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_sum.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_subqueries.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_truncate_table.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_hbase.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_txtfile.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_avro.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_parquet.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_rcfile.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_seqfile.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_shell_commands.xml"/></li>
+         <li><xref outputclass="release_2_3_0" href="impala_shell_options.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+
+      <concept id="release_2_2_3">
+        <title>CDH 5.4 / Impala 2.2.3</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_2_3" href="impala_datetime_functions.xml"/></li>
+         <li><xref outputclass="release_2_2_3" href="impala_parquet_file_size.xml"/></li>
+         <li><xref outputclass="release_2_2_3" href="impala_isilon.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+
+      <concept id="release_2_2_0">
+        <title>CDH 5.4 / Impala 2.2.0</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_2_0" href="impala_alter_table.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_alter_view.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_incompatible_changes.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_intro.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_compute_stats.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_create_database.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_create_table.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_create_view.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_ddl.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_dml.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_drop_database.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_drop_table.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_explain.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_insert.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_invalidate_metadata.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_conditional_functions.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_datetime_functions.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_faq.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_install.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_math_functions.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_conversion_functions.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_load_data.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_disk_space.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_tables.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_partitioning.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_refresh.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_select.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_show.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_scalability.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_timestamp.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_truncate_table.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_performance.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_explain_plan.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_perf_hdfs_caching.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_logging.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_s3.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_txtfile.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_parquet.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_lineage.xml"/></li>
+         <li><xref outputclass="release_2_2_0" href="impala_new_features.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+
+      <concept id="release_2_1_0">
+        <title>CDH 5.3 / Impala 2.1.0</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_1_0" href="impala_compute_stats.xml"/></li>
+         <li><xref outputclass="release_2_1_0" href="impala_drop_stats.xml"/></li>
+         <li><xref outputclass="release_2_1_0" href="impala_exec_single_node_rows_threshold.xml"/></li>
+         <li><xref outputclass="release_2_1_0" href="impala_reserved_words.xml"/></li>
+         <li><xref outputclass="release_2_1_0" href="impala_ports.xml"/></li>
+         <li><xref outputclass="release_2_1_0" href="impala_txtfile.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+
+      <concept id="release_2_0_1">
+        <title>CDH 5.2 / Impala 2.0.1</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_0_1" href="impala_perf_stats.xml"/></li>
+         <li><xref outputclass="release_2_0_1" href="impala_math_functions.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+
+      <concept id="release_2_0_0">
+        <title>CDH 5.2 / Impala 2.0.0</title>
+        <conbody>
+       <ul>
+         <li><xref outputclass="release_2_0_0" href="impala_appx_count_distinct.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_avg.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_incompatible_changes.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_char.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_compression_codec.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_count.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_create_function.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_create_table.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_ddl.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_disable_unsafe_spills.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_exec_single_node_rows_threshold.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_kerberos.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_grant.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_having.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_file_formats.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_analytic_functions.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_functions.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_datetime_functions.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_faq.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_misc_functions.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_perf_cookbook.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_prereqs.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_reserved_words.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_string_functions.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_udf.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_joins.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_limit.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_literals.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_max.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_min.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_ndv.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_query_timeout_s.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_hints.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_query_options.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_revoke.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_resource_management.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_set.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_show.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_operators.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_stddev.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_string.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_sum.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_timeouts.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_subqueries.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_txtfile.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_varchar.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_variance.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_shell_commands.xml"/></li>
+         <li><xref outputclass="release_2_0_0" href="impala_shell_options.xml"/></li>
+       </ul>
+
+</conbody>
+</concept>
+</concept>
+
+  <concept id="by_jira">
+    <title>Changes by JIRA Issue</title>
+    <conbody>
+      <p>
+        This section lists Impala-related issues from the Impala issue-tracking system.
+        These items represent new features, fixes for documentation bugs, and workarounds
+        and notices for code bugs or limitations.
+        The same text may be reused in identical form on multiple pages.
+        Use this section to cross-check the documentation changes for feature requests and
+        problem reports, and to see the details in the issue-tracking system for features
+        and fixes that are only mentioned briefly in the documentation, such as performance
+        improvements that do not require any user tuning actions.
+      </p>
+    </conbody>
+
+  <concept id="issue_IMPALA-3732">
+    <title>IMPALA-3732: Avro scanner can break on strings &gt;= 2GB</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3732">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3732" href="impala_char.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3732" href="impala_varchar.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3732" href="impala_avro.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3732" href="impala_string.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3679">
+    <title>IMPALA-3679: Zero copy reads don&#39;t work with encryption zones</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3679">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3679" href="impala_perf_hdfs_caching.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3662">
+    <title>IMPALA-3662: Parquet scanner memory increase after IMPALA-2736</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3662">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3662" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3581">
+    <title>IMPALA-3581: Change Default Minidump Location to /var/log/$daemon</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3581">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3581" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3558">
+    <title>IMPALA-3558: DROP TABLE PURGE on S3A table may not delete externally written files</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3558">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3558" href="impala_s3.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3558" href="impala_drop_table.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3554">
+    <title>IMPALA-3554: Use catalog&#39;s principal to talk to sentry in kerberized Impala clusters</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3554">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3554" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3554" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3490">
+    <title>IMPALA-3490: Add Flag to Cap Maximum Minidump Size</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3490">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3490" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3480">
+    <title>IMPALA-3480: Add query options to set min / max filter sizes</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3480">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3480" href="impala_runtime_filter_min_size.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3480" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3480" href="impala_runtime_filter_max_size.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3480" href="impala_runtime_filtering.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3471">
+    <title>IMPALA-3471: TopN should be able to spill</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3471">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3471" href="impala_scalability.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3471" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3453">
+    <title>IMPALA-3453: S3 : Uneven split sizes are generated for Parquet causing execution skew</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3453">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3453" href="impala_s3.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3453" href="impala_avro.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3453" href="impala_parquet.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3453" href="impala_select.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3453" href="impala_seqfile.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3453" href="impala_txtfile.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3453" href="impala_rcfile.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3452">
+    <title>IMPALA-3452: S3: Disable Impala staging for INSERTs via flag for speedup</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3452">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3452" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3452" href="impala_s3_skip_insert_staging.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3452" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3439">
+    <title>IMPALA-3439: Error choosing function signature in ROUND()</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3439">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3439" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3439" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3397">
+    <title>IMPALA-3397: Support SOURCE &lt;file&gt; in shell</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3397">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3397" href="impala_shell_running_commands.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3397" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3397" href="impala_shell_commands.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3375">
+    <title>IMPALA-3375: Investigate expensive calls to tc_delete_nothrow &amp; tc_new during TopN for 2x speedup.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3375">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3375" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3369">
+    <title>IMPALA-3369: Add a variant of alter table to manually add column stats</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3369">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3369" href="impala_alter_table.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3369" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3369" href="impala_perf_stats.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3333">
+    <title>IMPALA-3333: Enable global runtime filtering by default</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3333">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3333" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3333" href="impala_runtime_filtering.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3232">
+    <title>IMPALA-3232: Allow table refs in subqueries to refer to WITH-clause view in parent block.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3232">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3232" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3232" href="impala_operators.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3199">
+    <title>IMPALA-3199: Enable Admission Control by default (without limits)</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3199">Issue</xref></p>
+     <ul>
+<!--       <li><xref outputclass="issue_IMPALA-3199" href="admin_impala_admission_control.xml"/></li> -->
+       <li><xref outputclass="issue_IMPALA-3199" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3199" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3163">
+    <title>IMPALA-3163: DECIMAL casting to a TIMESTAMP doesn&#39;t keep precision</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3163">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3163" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3163" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3155">
+    <title>IMPALA-3155: CHAR expression in case statement is implicitly cast to string</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3155">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3155" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3155" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3095">
+    <title>IMPALA-3095: Allow additional Kerberos users to be authorized to access internal APIs</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3095">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3095" href="impala_kerberos.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3095" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3092">
+    <title>IMPALA-3092: Cannot query tables after add columns for AVRO table</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3092">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3092" href="impala_alter_table.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3092" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3077">
+    <title>IMPALA-3077: Runtime filters should be retained even when spilling</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3077">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3077" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3054">
+    <title>IMPALA-3054: Runtime filters are not disabled when spilling in a rare case</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3054">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3054" href="impala_scalability.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3054" href="impala_partitioning.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3054" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3054" href="impala_runtime_filtering.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3046">
+    <title>IMPALA-3046: Allow per-row filters to evaluate non-SlotRef exprs</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3046">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3046" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3044">
+    <title>IMPALA-3044: Fix admission control default value for max requests</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3044">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3044" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3039">
+    <title>IMPALA-3039: Restrict the number of runtime filters generated </title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3039">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3039" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3008">
+    <title>IMPALA-3008: Improve printing of filter routing table</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3008">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3008" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3007">
+    <title>IMPALA-3007: Use planner cardinality estimates when sizing bloom filters</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3007">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3007" href="impala_runtime_bloom_filter_size.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3007" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3007" href="impala_incompatible_changes.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-3007" href="impala_runtime_filtering.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-3001">
+    <title>IMPALA-3001: Improve usability of RUNTIME_FILTER query options</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-3001">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-3001" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2956">
+    <title>IMPALA-2956: Filters should be able to target multiple scans</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2956">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2956" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2867">
+    <title>IMPALA-2867: Load data inpath chokes on impala staging directories</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2867">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2867" href="impala_load_data.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2867" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2844">
+    <title>IMPALA-2844: Select count(*) from RCFileTable throw NotImplementedException in Impala 2.3.0</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2844">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2844" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2844" href="impala_avro.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2844" href="impala_complex_types.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2844" href="impala_seqfile.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2844" href="impala_txtfile.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2844" href="impala_rcfile.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2843">
+    <title>IMPALA-2843: Impala should read java udfs created from Hive</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2843">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2843" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2843" href="impala_create_function.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2843" href="impala_udf.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2843" href="impala_drop_function.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2835">
+    <title>IMPALA-2835: Hive/Impala inconsistency with parquet.column.index.access=false</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2835">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2835" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2835" href="impala_parquet.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2835" href="impala_parquet_fallback_schema_resolution.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2835" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2749">
+    <title>IMPALA-2749: Impala returns NULL when decimal and double values are multiplied in a specific order</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2749">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2749" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2749" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2736">
+    <title>IMPALA-2736: Column-wise value materialisation in Parquet scanner</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2736">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2736" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2728">
+    <title>IMPALA-2728: TestTpchMemLimitError.test_low_mem_limit_q21 exceeds mem_limit of 700M</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2728">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2728" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2696">
+    <title>IMPALA-2696: Simple scheduler always uses the same replica which can create hot spots</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2696">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2696" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2688">
+    <title>IMPALA-2688: Group by on Decimal data type doesn&#39;t get CodeGened </title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2688">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2688" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2686">
+    <title>IMPALA-2686: Implement google BreakPad based crash handler for impala.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2686">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2686" href="impala_breakpad.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2686" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2681">
+    <title>IMPALA-2681: Improve Decimal arithmetic performance by using a cheaper overflow check  </title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2681">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2681" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2660">
+    <title>IMPALA-2660: Respect auth_to_local rules from hdfs configs (core-site.xml)</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2660">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2660" href="impala_kerberos.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2660" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2660" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2641">
+    <title>IMPALA-2641: Add IF EXISTS clause to TRUNCATE TABLE statement</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2641">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2641" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2641" href="impala_truncate_table.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2599">
+    <title>IMPALA-2599: Pseudo-random sleep before acquiring kerberos ticket possibly not really pseudo-random.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2599">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2599" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2560">
+    <title>IMPALA-2560: Large memory consumption on coordinator node when handling a large number of partitions due to redundancy in TDescriptorTable</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2560">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2560" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2552">
+    <title>IMPALA-2552: Runtime filter forwarding between operators</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2552">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2552" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2538">
+    <title>IMPALA-2538: Per-pool default query memory limits</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2538">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2538" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2538" href="impala_admission.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2499">
+    <title>IMPALA-2499: Min/max values on partition columns</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2499">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2499" href="impala_partitioning.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2499" href="impala_optimize_partition_key_scans.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2499" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2419">
+    <title>IMPALA-2419: Extend Probe filter implementation</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2419">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2419" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2382">
+    <title>IMPALA-2382: Impala unable to read Java based UDFs that return a standard  datatype like Float or String(This works in hive)</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2382">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2382" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2336">
+    <title>IMPALA-2336: Failure to execute SQL scripts with trailing comments (including comment-only scripts)</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2336">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2336" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2257">
+    <title>IMPALA-2257: Text delimiter breaks data loading build</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2257">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2257" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2251">
+    <title>IMPALA-2251: Impala allows creation of text tables with same row and field delimiter</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2251">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2251" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2233">
+    <title>IMPALA-2233: Impala should not choose a function signature that results in loss of precision</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2233">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2233" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2204">
+    <title>IMPALA-2204: Underscore in where does not work for multi-line text </title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2204">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2204" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2196">
+    <title>IMPALA-2196: Add support for DESCRIBE DATABASE similar to Hive</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2196">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2196" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2196" href="impala_describe.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2180">
+    <title>IMPALA-2180:  IMPALA-2180: Extend SET command to allow setting variables in Impala Shell.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2180">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2180" href="impala_set.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2180" href="impala_shell_running_commands.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2180" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2180" href="impala_shell_commands.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2179">
+    <title>IMPALA-2179:  IMPALA-2179: Extend Impala shell to allow passing variables through the command line</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2179">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2179" href="impala_shell_running_commands.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2179" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2179" href="impala_impala_shell.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2147">
+    <title>IMPALA-2147: Support for null-safe equal/IS [NOT] DISTINCT FROM</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2147">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2147" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2130">
+    <title>IMPALA-2130: hdfs-parquet-scanner&#39;s verification of file version is not correct</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2130">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2130" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2111">
+    <title>IMPALA-2111: Parquet TIMESTAMP is in milliseconds</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2111">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2111" href="impala_timestamp.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2111" href="impala_parquet.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2111" href="impala_bigint.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2070">
+    <title>IMPALA-2070: Include the database comment when showing databases</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2070">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2070" href="impala_show.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2070" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2070" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-2069">
+    <title>IMPALA-2069: Cannot write string column to parquet with UTF-8 annotation</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-2069">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-2069" href="impala_parquet_annotate_strings_utf8.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2069" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-2069" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1934">
+    <title>IMPALA-1934: impala-shell to support reading password from command line when LDAP authentication is used</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1934">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1934" href="impala_shell_options.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1934" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1881">
+    <title>IMPALA-1881: Maximize data locality when scanning Parquet files with multiple row groups.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1881">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1881" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1878">
+    <title>IMPALA-1878: Support INSERT and LOAD DATA to S3</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1878">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_s3.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_alter_table.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_create_table.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_load_data.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_drop_database.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_insert.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_create_database.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1878" href="impala_drop_table.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1787">
+    <title>IMPALA-1787: Case-insensitivity modifier for regular expressions</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1787">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1787" href="impala_string_functions.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1787" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1772">
+    <title>IMPALA-1772: Additional date / time fns</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1772">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1772" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1771">
+    <title>IMPALA-1771: Hyperbolic trig fns etc.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1771">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1771" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1771" href="impala_math_functions.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1755">
+    <title>IMPALA-1755: Disabling codegen on parquet scanner causes some queries&#39; performance to regress</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1755">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1755" href="impala_scan_node_codegen_threshold.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1755" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1748">
+    <title>IMPALA-1748: Provide support for registering permanent udfs</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1748">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1748" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1748" href="impala_create_function.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1748" href="impala_udf.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1748" href="impala_incompatible_changes.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1748" href="impala_processes.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1748" href="impala_drop_function.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1740">
+    <title>IMPALA-1740: Impala cannot deal with skip.header.line.count</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1740">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1740" href="impala_new_features.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1740" href="impala_txtfile.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1675">
+    <title>IMPALA-1675: Timestamp: Adding/subtracting very large time intervals to timestamps produces incorrect result</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1675">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1675" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1651">
+    <title>IMPALA-1651: CREATE TABLE LIKE should not copy caching directives of the source table.</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1651">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1651" href="impala_incompatible_changes.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1599">
+    <title>IMPALA-1599: Improve query start-up time with many fragment instances</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1599">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1599" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1588">
+    <title>IMPALA-1588: Cache HDFS file handle to avoid repeated hdfs fopen call</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1588">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1588" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1568">
+    <title>IMPALA-1568: Find / repair missing partitions command</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1568">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1568" href="impala_alter_table.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1480">
+    <title>IMPALA-1480: Slow DDL statements for tables with large number of partitions</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1480">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1480" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1477">
+    <title>IMPALA-1477: Add UUID function</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1477">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1477" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1305">
+    <title>IMPALA-1305: Improve performance of high cardinality / low reduction aggs</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1305">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1305" href="impala_disable_streaming_preaggregations.xml"/></li>
+       <li><xref outputclass="issue_IMPALA-1305" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1168">
+    <title>IMPALA-1168: Finer grain Admission Control timeout control</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1168">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1168" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1139">
+    <title>IMPALA-1139: Implement TRUNCATE TABLE statement</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1139">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1139" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1079">
+    <title>IMPALA-1079: Impalad crashes while trying to run tpcds-q34</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1079">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1079" href="impala_shell_options.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  <concept id="issue_IMPALA-1067">
+    <title>IMPALA-1067: Passing Arguments through Impala Shell</title>
+    <conbody>
+      <p><xref scope="external" format="html" href="https://issues.cloudera.org/browse/IMPALA-1067">Issue</xref></p>
+     <ul>
+       <li><xref outputclass="issue_IMPALA-1067" href="impala_new_features.xml"/></li>
+     </ul>
+
+</conbody>
+</concept>
+
+  </concept>
+</concept>

http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3be0f122/docs/topics/impala_exec_single_node_rows_threshold.xml
----------------------------------------------------------------------
diff --git a/docs/topics/impala_exec_single_node_rows_threshold.xml b/docs/topics/impala_exec_single_node_rows_threshold.xml
new file mode 100644
index 0000000..a7cf102
--- /dev/null
+++ b/docs/topics/impala_exec_single_node_rows_threshold.xml
@@ -0,0 +1,96 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
+<concept rev="2.0.0" id="exec_single_node_rows_threshold">
+
+  <title>EXEC_SINGLE_NODE_ROWS_THRESHOLD Query Option (<keyword keyref="impala21"/> or higher only)</title>
+  <titlealts audience="PDF"><navtitle>EXEC_SINGLE_NODE_ROWS_THRESHOLD</navtitle></titlealts>
+  <prolog>
+    <metadata>
+      <data name="Category" value="Impala"/>
+      <data name="Category" value="Impala Query Options"/>
+      <data name="Category" value="Scalability"/>
+      <data name="Category" value="Performance"/>
+      <data name="Category" value="Developers"/>
+      <data name="Category" value="Data Analysts"/>
+    </metadata>
+  </prolog>
+
+  <conbody>
+
+    <p rev="2.0.0">
+      <indexterm audience="Cloudera">EXEC_SINGLE_NODE_ROWS_THRESHOLD query option</indexterm>
+      This setting controls the cutoff point (in terms of number of rows scanned) below which Impala treats a query
+      as a <q>small</q> query, turning off optimizations such as parallel execution and native code generation. The
+      overhead for these optimizations is applicable for queries involving substantial amounts of data, but it
+      makes sense to skip them for queries involving tiny amounts of data. Reducing the overhead for small queries
+      allows Impala to complete them more quickly, keeping YARN resources, admission control slots, and so on
+      available for data-intensive queries.
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/syntax_blurb"/>
+
+<codeblock>SET EXEC_SINGLE_NODE_ROWS_THRESHOLD=<varname>number_of_rows</varname></codeblock>
+
+    <p>
+      <b>Type:</b> numeric
+    </p>
+
+    <p>
+      <b>Default:</b> 100
+    </p>
+
+    <p>
+      <b>Usage notes:</b> Typically, you increase the default value to make this optimization apply to more queries.
+      If incorrect or corrupted table and column statistics cause Impala to apply this optimization
+      incorrectly to queries that actually involve substantial work, you might see the queries being slower as a
+      result of remote reads. In that case, recompute statistics with the <codeph>COMPUTE STATS</codeph>
+      or <codeph>COMPUTE INCREMENTAL STATS</codeph> statement. If there is a problem collecting accurate
+      statistics, you can turn this feature off by setting the value to -1.
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/internals_blurb"/>
+
+    <p>
+      This setting applies to query fragments where the amount of data to scan can be accurately determined, either
+      through table and column statistics, or by the presence of a <codeph>LIMIT</codeph> clause. If Impala cannot
+      accurately estimate the size of the input data, this setting does not apply.
+    </p>
+
+    <p rev="2.3.0">
+      In <keyword keyref="impala23_full"/> and higher, where Impala supports the complex data types <codeph>STRUCT</codeph>,
+      <codeph>ARRAY</codeph>, and <codeph>MAP</codeph>, if a query refers to any column of those types,
+      the small-query optimization is turned off for that query regardless of the
+      <codeph>EXEC_SINGLE_NODE_ROWS_THRESHOLD</codeph> setting.
+    </p>
+
+    <p>
+      For a query that is determined to be <q>small</q>, all work is performed on the coordinator node. This might
+      result in some I/O being performed by remote reads. The savings from not distributing the query work and not
+      generating native code are expected to outweigh any overhead from the remote reads.
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/added_in_210"/>
+
+    <p conref="../shared/impala_common.xml#common/example_blurb"/>
+
+    <p>
+      A common use case is to query just a few rows from a table to inspect typical data values. In this example,
+      Impala does not parallelize the query or perform native code generation because the result set is guaranteed
+      to be smaller than the threshold value from this query option:
+    </p>
+
+<codeblock>SET EXEC_SINGLE_NODE_ROWS_THRESHOLD=500;
+SELECT * FROM enormous_table LIMIT 300;
+</codeblock>
+
+<!-- Don't have any other places that tie into this particular optimization technique yet.
+Potentially: conceptual topics about code generation, distributed queries
+
+<p conref="../shared/impala_common.xml#common/related_info"/>
+<p>
+</p>
+-->
+
+  </conbody>
+
+</concept>

http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3be0f122/docs/topics/impala_explain.xml
----------------------------------------------------------------------
diff --git a/docs/topics/impala_explain.xml b/docs/topics/impala_explain.xml
new file mode 100644
index 0000000..81cc17b
--- /dev/null
+++ b/docs/topics/impala_explain.xml
@@ -0,0 +1,228 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
+<concept id="explain">
+
+  <title>EXPLAIN Statement</title>
+  <titlealts audience="PDF"><navtitle>EXPLAIN</navtitle></titlealts>
+  <prolog>
+    <metadata>
+      <data name="Category" value="Impala"/>
+      <data name="Category" value="SQL"/>
+      <data name="Category" value="Querying"/>
+      <data name="Category" value="Reports"/>
+      <data name="Category" value="Planning"/>
+      <data name="Category" value="Performance"/>
+      <data name="Category" value="Troubleshooting"/>
+      <data name="Category" value="Administrators"/>
+      <data name="Category" value="Developers"/>
+      <data name="Category" value="Data Analysts"/>
+    </metadata>
+  </prolog>
+
+  <conbody>
+
+    <p>
+      <indexterm audience="Cloudera">EXPLAIN statement</indexterm>
+      Returns the execution plan for a statement, showing the low-level mechanisms that Impala will use to read the
+      data, divide the work among nodes in the cluster, and transmit intermediate and final results across the
+      network. Use <codeph>explain</codeph> followed by a complete <codeph>SELECT</codeph> query. For example:
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/syntax_blurb"/>
+
+<codeblock>EXPLAIN { <varname>select_query</varname> | <varname>ctas_stmt</varname> | <varname>insert_stmt</varname> }
+</codeblock>
+
+    <p>
+      The <varname>select_query</varname> is a <codeph>SELECT</codeph> statement, optionally prefixed by a
+      <codeph>WITH</codeph> clause. See <xref href="impala_select.xml#select"/> for details.
+    </p>
+
+    <p>
+      The <varname>insert_stmt</varname> is an <codeph>INSERT</codeph> statement that inserts into or overwrites an
+      existing table. It can use either the <codeph>INSERT ... SELECT</codeph> or <codeph>INSERT ...
+      VALUES</codeph> syntax. See <xref href="impala_insert.xml#insert"/> for details.
+    </p>
+
+    <p>
+      The <varname>ctas_stmt</varname> is a <codeph>CREATE TABLE</codeph> statement using the <codeph>AS
+      SELECT</codeph> clause, typically abbreviated as a <q>CTAS</q> operation. See
+      <xref href="impala_create_table.xml#create_table"/> for details.
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/usage_notes_blurb"/>
+
+    <p>
+      You can interpret the output to judge whether the query is performing efficiently, and adjust the query
+      and/or the schema if not. For example, you might change the tests in the <codeph>WHERE</codeph> clause, add
+      hints to make join operations more efficient, introduce subqueries, change the order of tables in a join, add
+      or change partitioning for a table, collect column statistics and/or table statistics in Hive, or any other
+      performance tuning steps.
+    </p>
+
+    <p>
+      The <codeph>EXPLAIN</codeph> output reminds you if table or column statistics are missing from any table
+      involved in the query. These statistics are important for optimizing queries involving large tables or
+      multi-table joins. See <xref href="impala_compute_stats.xml#compute_stats"/> for how to gather statistics,
+      and <xref href="impala_perf_stats.xml#perf_stats"/> for how to use this information for query tuning.
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/explain_interpret"/>
+
+    <p>
+      If you come from a traditional database background and are not familiar with data warehousing, keep in mind
+      that Impala is optimized for full table scans across very large tables. The structure and distribution of
+      this data is typically not suitable for the kind of indexing and single-row lookups that are common in OLTP
+      environments. Seeing a query scan entirely through a large table is common, not necessarily an indication of
+      an inefficient query. Of course, if you can reduce the volume of scanned data by orders of magnitude, for
+      example by using a query that affects only certain partitions within a partitioned table, then you might be
+      able to optimize a query so that it executes in seconds rather than minutes.
+    </p>
+
+    <p>
+      For more information and examples to help you interpret <codeph>EXPLAIN</codeph> output, see
+      <xref href="impala_explain_plan.xml#perf_explain"/>.
+    </p>
+
+    <p rev="1.2">
+      <b>Extended EXPLAIN output:</b>
+    </p>
+
+    <p rev="1.2">
+      For performance tuning of complex queries, and capacity planning (such as using the admission control and
+      resource management features), you can enable more detailed and informative output for the
+      <codeph>EXPLAIN</codeph> statement. In the <cmdname>impala-shell</cmdname> interpreter, issue the command
+      <codeph>SET EXPLAIN_LEVEL=<varname>level</varname></codeph>, where <varname>level</varname> is an integer
+      from 0 to 3 or corresponding mnemonic values <codeph>minimal</codeph>, <codeph>standard</codeph>,
+      <codeph>extended</codeph>, or <codeph>verbose</codeph>.
+    </p>
+
+    <p rev="1.2">
+      When extended <codeph>EXPLAIN</codeph> output is enabled, <codeph>EXPLAIN</codeph> statements print
+      information about estimated memory requirements, minimum number of virtual cores, and so on.
+      <!--
+      that you can use to fine-tune the resource management options explained in <xref href="impala_resource_management.xml#rm_options"/>.
+      (The estimated memory requirements are intentionally on the high side, to allow a margin for error,
+      to avoid cancelling a query unnecessarily if you set the <codeph>MEM_LIMIT</codeph> option to the estimated memory figure.)
+      -->
+    </p>
+
+    <p>
+      See <xref href="impala_explain_level.xml#explain_level"/> for details and examples.
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/example_blurb"/>
+
+    <p>
+      This example shows how the standard <codeph>EXPLAIN</codeph> output moves from the lowest (physical) level to
+      the higher (logical) levels. The query begins by scanning a certain amount of data; each node performs an
+      aggregation operation (evaluating <codeph>COUNT(*)</codeph>) on some subset of data that is local to that
+      node; the intermediate results are transmitted back to the coordinator node (labelled here as the
+      <codeph>EXCHANGE</codeph> node); lastly, the intermediate results are summed to display the final result.
+    </p>
+
+<codeblock id="explain_plan_simple">[impalad-host:21000] &gt; explain select count(*) from customer_address;
++----------------------------------------------------------+
+| Explain String                                           |
++----------------------------------------------------------+
+| Estimated Per-Host Requirements: Memory=42.00MB VCores=1 |
+|                                                          |
+| 03:AGGREGATE [MERGE FINALIZE]                            |
+| |  output: sum(count(*))                                 |
+| |                                                        |
+| 02:EXCHANGE [PARTITION=UNPARTITIONED]                    |
+| |                                                        |
+| 01:AGGREGATE                                             |
+| |  output: count(*)                                      |
+| |                                                        |
+| 00:SCAN HDFS [default.customer_address]                  |
+|    partitions=1/1 size=5.25MB                            |
++----------------------------------------------------------+
+</codeblock>
+
+    <p>
+      These examples show how the extended <codeph>EXPLAIN</codeph> output becomes more accurate and informative as
+      statistics are gathered by the <codeph>COMPUTE STATS</codeph> statement. Initially, much of the information
+      about data size and distribution is marked <q>unavailable</q>. Impala can determine the raw data size, but
+      not the number of rows or number of distinct values for each column without additional analysis. The
+      <codeph>COMPUTE STATS</codeph> statement performs this analysis, so a subsequent <codeph>EXPLAIN</codeph>
+      statement has additional information to use in deciding how to optimize the distributed query.
+    </p>
+
+    <!-- To do:
+      Re-run these examples with more substantial tables populated with data.
+    -->
+
+<codeblock rev="1.2">[localhost:21000] &gt; set explain_level=extended;
+EXPLAIN_LEVEL set to extended
+[localhost:21000] &gt; explain select x from t1;
+[localhost:21000] &gt; explain select x from t1;
++----------------------------------------------------------+
+| Explain String                                           |
++----------------------------------------------------------+
+| Estimated Per-Host Requirements: Memory=32.00MB VCores=1 |
+|                                                          |
+| 01:EXCHANGE [PARTITION=UNPARTITIONED]                    |
+| |  hosts=1 per-host-mem=unavailable                      |
+<b>| |  tuple-ids=0 row-size=4B cardinality=unavailable       |</b>
+| |                                                        |
+| 00:SCAN HDFS [default.t2, PARTITION=RANDOM]              |
+|    partitions=1/1 size=36B                               |
+<b>|    table stats: unavailable                              |</b>
+<b>|    column stats: unavailable                             |</b>
+|    hosts=1 per-host-mem=32.00MB                          |
+<b>|    tuple-ids=0 row-size=4B cardinality=unavailable       |</b>
++----------------------------------------------------------+
+</codeblock>
+
+<codeblock rev="1.2">[localhost:21000] &gt; compute stats t1;
++-----------------------------------------+
+| summary                                 |
++-----------------------------------------+
+| Updated 1 partition(s) and 1 column(s). |
++-----------------------------------------+
+[localhost:21000] &gt; explain select x from t1;
++----------------------------------------------------------+
+| Explain String                                           |
++----------------------------------------------------------+
+| Estimated Per-Host Requirements: Memory=64.00MB VCores=1 |
+|                                                          |
+| 01:EXCHANGE [PARTITION=UNPARTITIONED]                    |
+| |  hosts=1 per-host-mem=unavailable                      |
+| |  tuple-ids=0 row-size=4B cardinality=0                 |
+| |                                                        |
+| 00:SCAN HDFS [default.t1, PARTITION=RANDOM]              |
+|    partitions=1/1 size=36B                               |
+<b>|    table stats: 0 rows total                             |</b>
+<b>|    column stats: all                                     |</b>
+|    hosts=1 per-host-mem=64.00MB                          |
+<b>|    tuple-ids=0 row-size=4B cardinality=0                 |</b>
++----------------------------------------------------------+
+</codeblock>
+
+    <p conref="../shared/impala_common.xml#common/security_blurb"/>
+    <p conref="../shared/impala_common.xml#common/redaction_yes"/>
+
+    <p conref="../shared/impala_common.xml#common/cancel_blurb_no"/>
+
+    <p conref="../shared/impala_common.xml#common/permissions_blurb"/>
+    <p rev="CDH-19187">
+      <!-- Doublecheck these details. Does EXPLAIN really need any permissions? -->
+      The user ID that the <cmdname>impalad</cmdname> daemon runs under,
+      typically the <codeph>impala</codeph> user, must have read
+      and execute permissions for all applicable directories in all source tables
+      for the query that is being explained.
+      (A <codeph>SELECT</codeph> operation could read files from multiple different HDFS directories
+      if the source table is partitioned.)
+    </p>
+
+    <p conref="../shared/impala_common.xml#common/related_info"/>
+    <p>
+      <xref href="impala_select.xml#select"/>,
+      <xref href="impala_insert.xml#insert"/>,
+      <xref href="impala_create_table.xml#create_table"/>,
+      <xref href="impala_explain_plan.xml#explain_plan"/>
+    </p>
+
+  </conbody>
+</concept>


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