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by evanelias 1129 days ago
Eh, just from a SQL query alone, there's no way to see that (lower(email)) is indexed, or see column data types etc. That metadata lives in the table definition, which is a normal place for it, so it seems reasonable for the collation / case-insensitivity to not be explicit in the query text.

Besides, MySQL also supports functional indexes, so you could do the (lower(email)) approach in MySQL too if you really want!

1 comments

No, you can't see everything, but you can see the exact comparison it's making. Is that useful? You can decide that for yourself but I like being able to see as much of the logic (and thus verify the correctness) in the query itself. Also helps with copy/paste and some other things.

I never said you can't use functional indexes in MySQL. Someone said "you can't do this in PostgreSQL" and I just commented "here's (one way) to do this, maybe that's helpful some day". That's it.

My apologies, I misunderstood "It's more explicit than MySQL" to imply that you were saying that approach couldn't be used in MySQL.