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0 pointsgaius8y ago0 comments

Was this a big deal in the past?

In MySQL, yes. It lacked the concept of foreign keys.

0 comments

Lack of foreign keys does not effect performance.

In fact, having foreign keys is a net-negative performance-wise because it means that each foreign key must be checked for every insert/update/delete.

branko_d8y ago

Foreign keys can improve performance, in some cases:

https://stackoverflow.com/a/8154375/533120

gaiusOP8y ago

Errm, we're talking about performance of joins

ComputerGuru8y ago

Joins will use the regular index matching it against the join condition just like a where clause would.

kondro8y ago

They don't help with that either.

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kondro8y ago

Lack of foreign keys does not effect performance.

In fact, having foreign keys is a net-negative performance-wise because it means that each foreign key must be checked for every insert/update/delete.

branko_d8y ago

Foreign keys can improve performance, in some cases:

https://stackoverflow.com/a/8154375/533120

gaiusOP8y ago

Errm, we're talking about performance of joins

ComputerGuru8y ago

Joins will use the regular index matching it against the join condition just like a where clause would.

kondro8y ago

They don't help with that either.

1 more reply

j / k navigate · click thread line to collapse