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https://issues.apache.org/jira/browse/HAWQ-1151?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15665479#comment-15665479
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ASF GitHub Bot commented on HAWQ-1151:
--------------------------------------

Github user dyozie commented on a diff in the pull request:

    https://github.com/apache/incubator-hawq-docs/pull/60#discussion_r87921640
  
    --- Diff: datamgmt/about_statistics.html.md.erb ---
    @@ -142,11 +142,28 @@ There are several options for configuring HAWQ 
statistics collection.
     
     The statistics target is the size of the `most_common_vals`, 
`most_common_freqs`, and `histogram_bounds` arrays for an individual column. By 
default, the target is 25. The default target can be changed by setting a 
server configuration parameter and the target can be set for any column using 
the `ALTER TABLE` command. Larger values increase the time needed to do 
`ANALYZE`, but may improve the quality of the legacy query optimizer (planner) 
estimates.
     
    -Set the system default statistics target to a different value by setting 
the `default_statistics_target` server configuration parameter. The default 
value is usually sufficient, and you should only raise or lower it if your 
tests demonstrate that query plans improve with the new target. For example, to 
raise the default statistics target from 25 to 50 you can use the `hawq config` 
utility:
    +Set the system default statistics target to a different value by setting 
the `default_statistics_target` server configuration parameter. The default 
value is usually sufficient, and you should only raise or lower it if your 
tests demonstrate that query plans improve with the new target. 
     
    -``` shell
    -$ hawq config -c default_statistics_target -v 50
    -```
    +You will perform different procedures to set server configuration 
parameters for your whole HAWQ cluster depending upon whether you manage your 
cluster from the command line or use Ambari. If you use Ambari to manage your 
HAWQ cluster, you must ensure that you update server configuration parameters 
via the Ambari Web UI only. If you manage your HAWQ cluster from the command 
line, you will use the `hawq config` command line utility to set server 
configuration parameters.
    +
    +For example, to raise the default statistics target from 25 to 50:
    --- End diff --
    
    Change to read "The following examples show how to raise the default 
statistics target from 25 to 50."


> docs - identify procedures for both ambari and CLI-managed clusters
> -------------------------------------------------------------------
>
>                 Key: HAWQ-1151
>                 URL: https://issues.apache.org/jira/browse/HAWQ-1151
>             Project: Apache HAWQ
>          Issue Type: Improvement
>          Components: Documentation
>            Reporter: Lisa Owen
>            Assignee: David Yozie
>             Fix For: 2.0.1.0-incubating
>
>
> different areas in the docs specify running "hawq config" to change server 
> configuration parameters.  the procedure is different in ambari managed 
> clusters. and, in fact you do NOT want to run `hawq config` in ambari managed 
> clusters.
> add specific notices and ambari procedures in the docs where appropriate.



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