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aiken
Aged Yak Warrior
525 Posts |
 Posted - 2002-04-15 : 19:50:41
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| I've got a "users" table that's at the heart of my app. At the moment, it has 16 FK's defined. I was about to add a few more, but for some reason I remember something about a 16 key limit.Did I dream that, or is there any kind of practical limit to foreign keys?Thanks-b |
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robvolk
Most Valuable Yak
15732 Posts |
Posted - 2002-04-15 : 20:46:40
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| Actually, a foreign key is limited to 16 columns per key, up to 253 foreign keys per table (SQL 2000, but I'm pretty sure it's the same for 7.0)Practically speaking, as long as your tables perform to your expectations with that many foreign keys, then stick with it. If adding more foreign keys affects performance negatively, then you might want to reconsider your table designs and denormalize them somewhat. |
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aiken
Aged Yak Warrior
525 Posts |
Posted - 2002-04-15 : 21:02:55
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| Ah, ok, I was confusing the 16 and 253 limits. 253 should be fine.Things seem fine with the number of keys now. I do have checks turned off on a few of the keys that affect tables with high insert volumes.Cheers-b |
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Any limit to foreign keys?