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Unified Queries for Java
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provide support for relational division #1121

Closed SebastianDietrich closed 3 years ago

SebastianDietrich commented 9 years ago

Please provide support for relational division. E.g. like JOOQ supports it (http://www.jooq.org/doc/3.0/manual-single-page/#relational-division).

Either the "classical version" or the "reduced version" - http://jise.org/Volume13/Pdf/085.pdf

lukaseder commented 9 years ago

One of the best articles on the subject has been written by Joe Celko whom I need not introduce: https://www.simple-talk.com/sql/t-sql-programming/divided-we-stand-the-sql-of-relational-division

Division is hard to get right. A whole chain of SQL transformation capabilities need to be put in place. I wouldn't add this feature without giving the whole transformation tool chain some thorough thought.

SebastianDietrich commented 9 years ago

You are right - division is hard to get right. That's the main reason for my request :-) The second reason is that it is hard to read. A one-liner like JOOQ-division would help a lot.

stale[bot] commented 3 years ago

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.