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From bpendle...@apache.org
Subject svn commit: r773294 [2/2] - in /db/derby/docs/trunk/src: ref/ tuning/
Date Sun, 10 May 2009 02:07:08 GMT
Added: db/derby/docs/trunk/src/tuning/ctun_xplain_tables.dita
URL: http://svn.apache.org/viewvc/db/derby/docs/trunk/src/tuning/ctun_xplain_tables.dita?rev=773294&view=auto
==============================================================================
--- db/derby/docs/trunk/src/tuning/ctun_xplain_tables.dita (added)
+++ db/derby/docs/trunk/src/tuning/ctun_xplain_tables.dita Sun May 10 02:07:07 2009
@@ -0,0 +1,126 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- 
+Licensed to the Apache Software Foundation (ASF) under one or more
+contributor license agreements.  See the NOTICE file distributed with
+this work for additional information regarding copyright ownership.
+The ASF licenses this file to You under the Apache License, Version 2.0
+(the "License"); you may not use this file except in compliance with
+the License.  You may obtain a copy of the License at      
+
+http://www.apache.org/licenses/LICENSE-2.0  
+
+Unless required by applicable law or agreed to in writing, software  
+distributed under the License is distributed on an "AS IS" BASIS,  
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  
+See the License for the specific language governing permissions and  
+limitations under the License.
+-->
+
+<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "../dtd/concept.dtd">
+<concept xml:lang="en-us" id="ctun_xplain_tables">
+<title>Understanding XPLAIN style database tables</title>
+<prolog><metadata>
+<keywords>
+    <indexterm>XPLAIN style</indexterm>
+</keywords>
+</metadata>
+</prolog>
+<conbody>
+    <p>
+        XPLAIN style is an enhanced form of RUNTIMESTATISTICS processing
+        which preserves captured statistics information in database tables.
+        Once the statistics have been collected and saved in the 
+        tables, they can be queried for analysis purposes.
+    </p>
+    <p>
+        Rows accumulate in the SYSXPLAIN_* database tables until you 
+        empty the tables by dropping them or executing DELETE FROM statements
+        against them.
+    </p>
+    <p>
+        Note that, although these tables have stylized names which all
+        start with the prefix "SYSXPLAIN_*", they are not in fact special
+        system catalogs, but are merely ordinary database tables, which
+        can be accessed in all the standard ways that any other database
+        table is accessed. The tables are automatically created if they
+        are not present when statistics are being captured. The tables
+        are all located in a particular schema which is specified by the
+        <codeph>SYSCS_UTIL.SYSCS_SET_XPLAIN_SCHEMA()</codeph> system procedure.
+    </p>
+    <p>
+        The XPLAIN style database tables are summarized here. For more
+        information about the structure and content of each table,
+        please see the <ph conref="../conrefs.dita#pub/citref"></ph> for
+        <xref href="../ref/rref_xplain_tables.dita#rref_xplain_tables">
+            detailed table descriptions</xref>.
+    </p>
+    <dl>
+        <dlentry>
+        <dt>SYSXPLAIN_STATEMENTS</dt>
+        <dd>This table contains one row for each statement which
+            has had statistics captured. This row contains the text of the
+            statement, as well as identifiers which can be used to join with
+            the other tables to find more data about how this statement was
+            executed. The
+        <ph conref="../conrefs.dita#pub/citref"></ph> contains
+        <xref href="../ref/rrefsysxplain_statements.dita#rrefsysxplain_statements">
+            detailed table information</xref>
+        </dd>
+        </dlentry>
+        <dlentry>
+        <dt>SYSXPLAIN_RESULTSETS</dt>
+        <dd>This table contains one row for each result set which
+            was used during the execution of a particular explained statement.
+            Most queries have one or several result sets; some complex queries
+        can have many result sets.
+        The <ph conref="../conrefs.dita#pub/citref"></ph> contains
+        <xref href="../ref/rrefsysxplain_resultsets.dita#rrefsysxplain_resultsets">
+            detailed table information</xref>
+        </dd>
+        </dlentry>
+        <dlentry>
+        <dt>SYSXPLAIN_SCAN_PROPS</dt>
+        <dd>This table contains one row for each result set which
+            performed a scan of a table, index, or constraint. Using the
+            information in this row, you can determine how much data needed
+        to be examined by the scan.
+        The <ph conref="../conrefs.dita#pub/citref"></ph> contains
+        <xref href="../ref/rrefsysxplain_scan_props.dita#rrefsysxplain_scan_props">
+            detailed table information</xref>
+        </dd>
+        </dlentry>
+        <dlentry>
+        <dt>SYSXPLAIN_SORT_PROPS</dt>
+        <dd>This table contains one row for each result set which
+            performed a sort of data. Using the information in this row, you
+        can determine how much data needed to be sorted.
+        The <ph conref="../conrefs.dita#pub/citref"></ph> contains
+        <xref href="../ref/rrefsysxplain_sort_props.dita#rrefsysxplain_sort_props">
+            detailed table information</xref>
+        </dd>
+        </dlentry>
+        <dlentry>
+        <dt>SYSXPLAIN_STATEMENT_TIMINGS</dt>
+        <dd>This table contains timing information at the statement
+            level. Timing information is optional, but if it is captured, the
+            data in this table can be used to determine how much time each
+        statement took.
+        The <ph conref="../conrefs.dita#pub/citref"></ph> contains
+        <xref href="../ref/rrefsysxplain_statement_timings.dita#rrefsysxplain_statement_timings">
+            detailed table information</xref>
+        </dd>
+        </dlentry>
+        <dlentry>
+        <dt>SYSXPLAIN_RESULTSET_TIMINGS</dt>
+        <dd>This table contains timing information at the result set
+            level. Timing information is optional, but if it is captured, the
+            data in this table can be used to determine how much time each
+        result set took.
+        The <ph conref="../conrefs.dita#pub/citref"></ph> contains
+        <xref href="../ref/rrefsysxplain_resultset_timings.dita#rrefsysxplain_resultset_timings">
+            detailed table information</xref>
+        </dd>
+        </dlentry>
+    </dl>
+</conbody></concept>
+

Propchange: db/derby/docs/trunk/src/tuning/ctun_xplain_tables.dita
------------------------------------------------------------------------------
    svn:eol-style = native

Modified: db/derby/docs/trunk/src/tuning/ctundepth26674.dita
URL: http://svn.apache.org/viewvc/db/derby/docs/trunk/src/tuning/ctundepth26674.dita?rev=773294&r1=773293&r2=773294&view=diff
==============================================================================
--- db/derby/docs/trunk/src/tuning/ctundepth26674.dita (original)
+++ db/derby/docs/trunk/src/tuning/ctundepth26674.dita Sun May 10 02:07:07 2009
@@ -41,5 +41,16 @@
 rewrite queries.</p></li>
 </ul></p>
 <p>The exact details presented, as well as the format of presentation, can
-change. </p>
+    change. There are two techniques for retrieving the RUNTIMESTATISTICS
+    information:
+    <ul>
+        <li>call SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS, which retrieves
+            the RUNTIMESTATISTICS information as formatted text</li>
+        <li>call SYSCS_UTIL.SYSCS_SET_XPLAIN_SCHEMA before executing your
+            statements, which causes 
+            <ph conref="../conrefs.dita#prod/productshortname"></ph>
+            to store the RUNTIMESTATISTICS information in the SYSXPLAIN 
+            database tables, which can then be queried 
+            later to retrieve the data.</li>
+</ul></p>
 </conbody></concept>

Modified: db/derby/docs/trunk/src/tuning/tuningderby.ditamap
URL: http://svn.apache.org/viewvc/db/derby/docs/trunk/src/tuning/tuningderby.ditamap?rev=773294&r1=773293&r2=773294&view=diff
==============================================================================
--- db/derby/docs/trunk/src/tuning/tuningderby.ditamap (original)
+++ db/derby/docs/trunk/src/tuning/tuningderby.ditamap Sun May 10 02:07:07 2009
@@ -101,12 +101,14 @@
 <topicref href="ctundepth26674.dita" navtitle="Overview"></topicref>
 <topicref href="ttundepth34375.dita" navtitle="How you use the RUNTIMESTATISTICS attribute">
 </topicref>
+<topicref href="ctun_xplain_style.dita" navtitle="How you use the XPLAIN style"></topicref>
 <topicref collection-type="family" href="ctundepth37648.dita" navtitle="Analyzing the
information">
 <topicref href="ctundepth853095.dita" navtitle="Statistics timing"></topicref>
 <topicref href="ctundepth853133.dita" navtitle="Statement execution plan">
 </topicref>
 <topicref href="ctundepth853228.dita" navtitle="Optimizer estimates"></topicref>
 <topicref href="ctundepthoptover.dita" navtitle="Optimizer overrides"></topicref>
+<topicref href="ctun_xplain_tables.dita" navtitle="Understanding XPLAIN style database
tables"></topicref>
 </topicref>
 </topicref>
 </topicref>



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