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From "Craig L Russell (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (JDO-730) Creating the innerjoin without relationship between objects
Date Fri, 11 Jul 2014 16:52:06 GMT

    [ https://issues.apache.org/jira/browse/JDO-730?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14058996#comment-14058996
] 

Craig L Russell commented on JDO-730:
-------------------------------------

Using a variable to identify the second table should result in the additional table in the
FROM clause. The condition should then appear in the WHERE clause of the query. Putting the
condition into the JOIN clause is simply SQL shorthand. The optimizer should not generate
a different execution plan for the two queries.

If this doesn't make sense, please post the SQL that you would like to see and its execution
plan and then the generated SQL with its execution plan so we can understand your concern.

> Creating the innerjoin without relationship between objects
> -----------------------------------------------------------
>
>                 Key: JDO-730
>                 URL: https://issues.apache.org/jira/browse/JDO-730
>             Project: JDO
>          Issue Type: Wish
>          Components: api
>    Affects Versions: JDO 3.1-rc1
>            Reporter: RaviRaja
>            Assignee: Michael Bouschen
>             Fix For: JDO 3.1
>
>
> Cannot make innerjoin like this without relationship:
> select a.x, b.y from Table1 as a INNER JOIN Table 2 as b ON a.z=b.w
> Note: a.z and b.w are not primary and foreign keys



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