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by masklinn 1330 days ago
> When you're escaping a LIKE expression for other databases, you must not escape the "[" character, since some databases reject escaping anything other than the % and _ wildcards. That is, your escaping code for a LIKE expression has to be database-specific, because MSSQL (and AFAIK Sybase, it seems both have a common ancestor) decided to be different.

TBF you may need custom codepaths because defaults diverge as well, IIRC postgres and sqlite default to ESCAPE '\' while mssql and oracle default to ESCAPE '' (the latter being the actual spec behaviour).

So in Postgres and SQLite you must always escape your LIKE parameter, while in mssql and oracle that's not the case.

1 comments

> TBF you may need custom codepaths because defaults diverge as well, IIRC postgres and sqlite default to ESCAPE '\' while mssql and oracle default to ESCAPE '' (the latter being the actual spec behaviour).

The trick is to just avoid the default, and always use an explicit ESCAPE, which should work the same on every database (except mysql without NO_BACKSLASH_ESCAPES in which you also have to escape the backslash itself, otherwise it will escape the closing quote and get very confused, but that issue can be avoided by using a character other than backslash as the escape character).