Joins

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quickvfr
Posts: 21
Joined: Tue Oct 10, 2017 12:44 pm

Joins

Post by quickvfr » Mon Jun 08, 2009 4:06 pm

I have a couple of reports that I have added an additional joins to and the performance has gone from 3 minutes to hours (if it finishes at all). All the new join is used for is to limit master table records by subcategories (make the join and then filter by "is not null" dropdown refering to the new table). Any suggestions would be greatly appreciated.

chibbert
Posts: 9
Joined: Tue Oct 10, 2017 12:44 pm

=> RE: Joins

Post by chibbert » Mon Jun 08, 2009 4:53 pm

Not seeing your data, it is possible that your join needs to have more than one rule.____If you have table A with 5 million records and table B with 5 million records and you join on a single field, you are asking for a possibility of 2.5 x 10 to the 13th power results. However if you join on more than one condition, you may reduce that down to 10,000 results.____I am probably doing a poor job of explaining but it^s an attempt :)

quickvfr
Posts: 21
Joined: Tue Oct 10, 2017 12:44 pm

==> RE: Joins

Post by quickvfr » Mon Jun 08, 2009 5:43 pm

Thank you! I learned something new today. Worked like a charm. We just transitioned off of DBF^s and this was the first real hurdle in SQL. Thank you!

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