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From shaofeng...@apache.org
Subject kylin git commit: add timezone in jdbc to faq
Date Mon, 05 Feb 2018 00:51:18 GMT
Repository: kylin
Updated Branches:
  refs/heads/document 7187b6e7f -> fbacaf23c


add timezone in jdbc to faq


Project: http://git-wip-us.apache.org/repos/asf/kylin/repo
Commit: http://git-wip-us.apache.org/repos/asf/kylin/commit/fbacaf23
Tree: http://git-wip-us.apache.org/repos/asf/kylin/tree/fbacaf23
Diff: http://git-wip-us.apache.org/repos/asf/kylin/diff/fbacaf23

Branch: refs/heads/document
Commit: fbacaf23c3acefd97536b5b1ffc8efc4c637c50e
Parents: 7187b6e
Author: shaofengshi <shaofengshi@apache.org>
Authored: Mon Feb 5 08:51:13 2018 +0800
Committer: shaofengshi <shaofengshi@apache.org>
Committed: Mon Feb 5 08:51:13 2018 +0800

----------------------------------------------------------------------
 website/_docs23/gettingstarted/faq.md | 32 ++++++++++--------------------
 1 file changed, 10 insertions(+), 22 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/kylin/blob/fbacaf23/website/_docs23/gettingstarted/faq.md
----------------------------------------------------------------------
diff --git a/website/_docs23/gettingstarted/faq.md b/website/_docs23/gettingstarted/faq.md
index e02acfe..c9a8998 100644
--- a/website/_docs23/gettingstarted/faq.md
+++ b/website/_docs23/gettingstarted/faq.md
@@ -26,21 +26,8 @@ since: v0.6.x
 
   * Kylin uses "Dictionary" encoding to encode/decode the dimension values (check [this blog](/blog/2015/08/13/kylin-dictionary/));
Usually a dimension's cardinality is less than millions, so the "Dict" encoding is good to
use. As dictionary need be persisted and loaded into memory, if a dimension's cardinality
is very high, the memory footprint will be tremendous, so Kylin add a check on this. If you
see this error, suggest to identify the UHC dimension first and then re-evaluate the design
(whether need to make that as dimension?). If must keep it, you can by-pass this error with
couple ways: 1) change to use other encoding (like `fixed_length`, `integer`) 2) or set a
bigger value for `kylin.dictionary.max.cardinality` in `conf/kylin.properties`.
 
-#### 3. Build cube failed due to "error check status"
 
-  * Check if `kylin.log` contains *yarn.resourcemanager.webapp.address:http://0.0.0.0:8088*
and *java.net.ConnectException: Connection refused*
-  * If yes, then the problem is the address of resource manager was not available in yarn-site.xml
-  * A workaround is update `kylin.properties`, set `kylin.job.yarn.app.rest.check.status.url=http://YOUR_RM_NODE:8088/ws/v1/cluster/apps/${job_id}?anonymous=true`
-
-#### 4. HBase cannot get master address from ZooKeeper on Hortonworks Sandbox
-   
-  * By default hortonworks disables hbase, you'll have to start hbase in ambari homepage
first.
-
-#### 5. Map Reduce Job information cannot display on Hortonworks Sandbox
-   
-  * Check out [https://github.com/KylinOLAP/Kylin/issues/40](https://github.com/KylinOLAP/Kylin/issues/40)
-
-#### 6. How to Install Kylin on CDH 5.2 or Hadoop 2.5.x
+#### 3. How to Install Kylin on CDH 5.2 or Hadoop 2.5.x
 
   * Check out discussion: [https://groups.google.com/forum/?utm_medium=email&utm_source=footer#!msg/kylin-olap/X0GZfsX1jLc/nzs6xAhNpLkJ](https://groups.google.com/forum/?utm_medium=email&utm_source=footer#!msg/kylin-olap/X0GZfsX1jLc/nzs6xAhNpLkJ)
 
@@ -55,16 +42,16 @@ since: v0.6.x
   {% endhighlight %}
 
 
-#### 7. SUM(field) returns a negtive result while all the numbers in this field are >
0
+#### 4. SUM(field) returns a negtive result while all the numbers in this field are >
0
   * If a column is declared as integer in Hive, the SQL engine (calcite) will use column's
type (integer) as the data type for "SUM(field)", while the aggregated value on this field
may exceed the scope of integer; in that case the cast will cause a negtive value be returned;
The workround is, alter that column's type to BIGINT in hive, and then sync the table schema
to Kylin (the cube doesn't need rebuild); Keep in mind that, always declare as BIGINT in hive
for an integer column which would be used as a measure in Kylin; See hive number types: [https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Types#LanguageManualTypes-NumericTypes](https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Types#LanguageManualTypes-NumericTypes)
 
-#### 8. Why Kylin need extract the distinct columns from Fact Table before building cube?
+#### 5. Why Kylin need extract the distinct columns from Fact Table before building cube?
   * Kylin uses dictionary to encode the values in each column, this greatly reduce the cube's
storage size. To build the dictionary, Kylin need fetch the distinct values for each column.
 
-#### 9. Why Kylin calculate the HIVE table cardinality?
+#### 6. Why Kylin calculate the HIVE table cardinality?
   * The cardinality of dimensions is an important measure of cube complexity. The higher
the cardinality, the bigger the cube, and thus the longer to build and the slower to query.
Cardinality > 1,000 is worth attention and > 1,000,000 should be avoided at best effort.
For optimal cube performance, try reduce high cardinality by categorize values or derive features.
 
-#### 10. How to add new user or change the default password?
+#### 7. How to add new user or change the default password?
   * Kylin web's security is implemented with Spring security framework, where the kylinSecurity.xml
is the main configuration file:
 
    {% highlight Groff markup %}
@@ -74,7 +61,7 @@ since: v0.6.x
   * The password hash for pre-defined test users can be found in the profile "sandbox,testing"
part; To change the default password, you need generate a new hash and then update it here,
please refer to the code snippet in: [https://stackoverflow.com/questions/25844419/spring-bcryptpasswordencoder-generate-different-password-for-same-input](https://stackoverflow.com/questions/25844419/spring-bcryptpasswordencoder-generate-different-password-for-same-input)
   * When you deploy Kylin for more users, switch to LDAP authentication is recommended.
 
-#### 11. Using sub-query for un-supported SQL
+#### 8. Using sub-query for un-supported SQL
 
 {% highlight Groff markup %}
 Original SQL:
@@ -103,7 +90,7 @@ from (
 group by a.slr_sgmt
 {% endhighlight %}
 
-#### 12. Build kylin meet NPM errors (中国大陆地区用户请特别注意此问题)
+#### 9. Build kylin meet NPM errors (中国大陆地区用户请特别注意此问题)
 
   * Please add proxy for your NPM:  
   `npm config set proxy http://YOUR_PROXY_IP`
@@ -111,9 +98,10 @@ group by a.slr_sgmt
   * Please update your local NPM repository to using any mirror of npmjs.org, like Taobao
NPM (请更新您本地的NPM仓库以使用国内的NPM镜像,例如淘宝NPM镜像) :
 
   [http://npm.taobao.org](http://npm.taobao.org)
 
-#### 13. Failed to run BuildCubeWithEngineTest, saying failed to connect to hbase while hbase
is active
+#### 10. Failed to run BuildCubeWithEngineTest, saying failed to connect to hbase while hbase
is active
   * User may get this error when first time run hbase client, please check the error trace
to see whether there is an error saying couldn't access a folder like "/hadoop/hbase/local/jars";
If that folder doesn't exist, create it.
 
-
+#### 11. Kylin JDBC driver returns a different Date/time than the REST API, seems it add
the timezone to parse the date.
+  * Please check the [post in mailing list](http://apache-kylin.74782.x6.nabble.com/JDBC-query-result-Date-column-get-wrong-value-td5370.html)
 
 


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