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Posted to commits@kylin.apache.org by li...@apache.org on 2016/05/09 07:51:16 UTC
kylin git commit: Refine FAQ
Repository: kylin
Updated Branches:
refs/heads/document b407e188f -> 20cfd0fa6
Refine FAQ
Project: http://git-wip-us.apache.org/repos/asf/kylin/repo
Commit: http://git-wip-us.apache.org/repos/asf/kylin/commit/20cfd0fa
Tree: http://git-wip-us.apache.org/repos/asf/kylin/tree/20cfd0fa
Diff: http://git-wip-us.apache.org/repos/asf/kylin/diff/20cfd0fa
Branch: refs/heads/document
Commit: 20cfd0fa6f4a5da34630f4b1ce044d944e584edf
Parents: b407e18
Author: Li Yang <li...@apache.org>
Authored: Mon May 9 15:51:03 2016 +0800
Committer: Li Yang <li...@apache.org>
Committed: Mon May 9 15:51:03 2016 +0800
----------------------------------------------------------------------
website/_docs15/gettingstarted/faq.md | 80 +++++++++++++++++-------------
1 file changed, 46 insertions(+), 34 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/kylin/blob/20cfd0fa/website/_docs15/gettingstarted/faq.md
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diff --git a/website/_docs15/gettingstarted/faq.md b/website/_docs15/gettingstarted/faq.md
index bbb3343..4306813 100644
--- a/website/_docs15/gettingstarted/faq.md
+++ b/website/_docs15/gettingstarted/faq.md
@@ -6,55 +6,55 @@ permalink: /docs15/gettingstarted/faq.html
since: v0.6.x
---
-### Some NPM error causes ERROR exit (\u4e2d\u56fd\u5927\u9646\u5730\u533a\u7528\u6237\u8bf7\u7279\u522b\u6ce8\u610f\u6b64\u95ee\u9898)?
-For people from China:
+#### Build cube failed due to "error check status"
-* Please add proxy for your NPM (\u8bf7\u4e3aNPM\u8bbe\u7f6e\u4ee3\u7406):
-`npm config set proxy http://YOUR_PROXY_IP`
+ * 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`
-* Please update your local NPM repository to using any mirror of npmjs.org, like Taobao NPM (\u8bf7\u66f4\u65b0\u60a8\u672c\u5730\u7684NPM\u4ed3\u5e93\u4ee5\u4f7f\u7528\u56fd\u5185\u7684NPM\u955c\u50cf\uff0c\u4f8b\u5982\u6dd8\u5b9dNPM\u955c\u50cf) :
-[http://npm.taobao.org](http://npm.taobao.org)
+#### 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.
-### Can't get master address from ZooKeeper" when installing Kylin on Hortonworks Sandbox
-Check out [https://github.com/KylinOLAP/Kylin/issues/9](https://github.com/KylinOLAP/Kylin/issues/9).
-
-### Map Reduce Job information can't display on sandbox deployment
-Check out [https://github.com/KylinOLAP/Kylin/issues/40](https://github.com/KylinOLAP/Kylin/issues/40)
+#### 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)
#### 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)
-{% highlight Groff markup %}
-I was able to deploy Kylin with following option in POM.
-<hadoop2.version>2.5.0</hadoop2.version>
-<yarn.version>2.5.0</yarn.version>
-<hbase-hadoop2.version>0.98.6-hadoop2</hbase-hadoop2.version>
-<zookeeper.version>3.4.5</zookeeper.version>
-<hive.version>0.13.1</hive.version>
-My Cluster is running on Cloudera Distribution CDH 5.2.0.
-{% endhighlight %}
-#### Unable to load a big cube as HTable, with java.lang.OutOfMemoryError: unable to create new native thread
-HBase (as of writing) allocates one thread per region when bulk loading a HTable. Try reduce the number of regions of your cube by setting its "capacity" to "MEDIUM" or "LARGE". Also tweaks OS & JVM can allow more threads, for example see [this article](http://blog.egilh.com/2006/06/2811aspx.html).
+ * 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)
-#### 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.
+ {% highlight Groff markup %}
+ I was able to deploy Kylin with following option in POM.
+ <hadoop2.version>2.5.0</hadoop2.version>
+ <yarn.version>2.5.0</yarn.version>
+ <hbase-hadoop2.version>0.98.6-hadoop2</hbase-hadoop2.version>
+ <zookeeper.version>3.4.5</zookeeper.version>
+ <hive.version>0.13.1</hive.version>
+ My Cluster is running on Cloudera Distribution CDH 5.2.0.
+ {% endhighlight %}
+
+#### Unable to load a big cube as HTable, with java.lang.OutOfMemoryError: unable to create new native thread
+ * HBase (as of writing) allocates one thread per region when bulk loading a HTable. Try reduce the number of regions of your cube by setting its "capacity" to "MEDIUM" or "LARGE". Also tweaks OS & JVM can allow more threads, for example see [this article](http://blog.egilh.com/2006/06/2811aspx.html).
#### 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)
+ * 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)
#### 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.
+ * 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.
#### 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.
+ * 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.
#### 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 %}
-${KYLIN_HOME}/tomcat/webapps/kylin/WEB-INF/classes/kylinSecurity.xml
-{% endhighlight %}
-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; To enable LDAP authentication, update "kylin.sandbox" in conf/kylin.properties to false, and also configure the ldap.* properties in ${KYLIN_HOME}/conf/kylin.properties
+ * Kylin web's security is implemented with Spring security framework, where the kylinSecurity.xml is the main configuration file:
+
+ {% highlight Groff markup %}
+ ${KYLIN_HOME}/tomcat/webapps/kylin/WEB-INF/classes/kylinSecurity.xml
+ {% endhighlight %}
+
+ * 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; To enable LDAP authentication, update "kylin.sandbox" in conf/kylin.properties to false, and also configure the ldap.* properties in ${KYLIN_HOME}/conf/kylin.properties
#### Using sub-query for un-supported SQL
@@ -85,5 +85,17 @@ from (
group by a.slr_sgmt
{% endhighlight %}
+#### Build kylin meet NPM errors (\u4e2d\u56fd\u5927\u9646\u5730\u533a\u7528\u6237\u8bf7\u7279\u522b\u6ce8\u610f\u6b64\u95ee\u9898)?
+
+ * Please add proxy for your NPM (\u8bf7\u4e3aNPM\u8bbe\u7f6e\u4ee3\u7406):
+ `npm config set proxy http://YOUR_PROXY_IP`
+
+ * Please update your local NPM repository to using any mirror of npmjs.org, like Taobao NPM (\u8bf7\u66f4\u65b0\u60a8\u672c\u5730\u7684NPM\u4ed3\u5e93\u4ee5\u4f7f\u7528\u56fd\u5185\u7684NPM\u955c\u50cf\uff0c\u4f8b\u5982\u6dd8\u5b9dNPM\u955c\u50cf) :
+ [http://npm.taobao.org](http://npm.taobao.org)
+
+#### 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.
+
+