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https://issues.apache.org/jira/browse/PHOENIX-953?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14682199#comment-14682199
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Julian Hyde commented on PHOENIX-953:
-------------------------------------

By the way, Postgres' 'UNNEST' reminds me of LINQ's 'selectMany' operator 
https://msdn.microsoft.com/en-us/library/system.linq.enumerable.selectmany(v=vs.100).aspx
 , which is well defined and powerful and could even be added to SQL in some 
form.

Unlike Postgres' SELECT-with-UNNEST, selectMany takes just one argument, which 
must be a collection.

> Support UNNEST for ARRAY
> ------------------------
>
>                 Key: PHOENIX-953
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-953
>             Project: Phoenix
>          Issue Type: Sub-task
>            Reporter: James Taylor
>            Assignee: Dumindu Buddhika
>         Attachments: PHOENIX-953-v1.patch
>
>
> The UNNEST built-in function converts an array into a set of rows. This is 
> more than a built-in function, so should be considered an advanced project.
> For an example, see the following Postgres documentation: 
> http://www.postgresql.org/docs/8.4/static/functions-array.html
> http://www.anicehumble.com/2011/07/postgresql-unnest-function-do-many.html
> http://tech.valgog.com/2010/05/merging-and-manipulating-arrays-in.html
> So the UNNEST is a way of converting an array to a flattened "table" which 
> can then be filtered on, ordered, grouped, etc.



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