Re: [SQL] How match percent sign in SELECT using LIKE?

> One useful and probably not too hard thing to do is to allow ESCAPE '\' on
> the end of the LIKE clause. Any character other than '\' will be an error.
> This allows Postgres users to write compliant SQL code that can be used
> with other databases.

This is an excellent idea, I will implement it.

>
> Another approach is to "rewrite" the match string at parse time. If it is a
> known constant, you can do the whole job there. Otherwise, you'd insert an
> extra node in the parse tree which does the rewrite just before calling hte
> "~~" operator. (I am assuming the match string can be a general expression
> and that you can add a function of two arguments which rewrites the first
> argument using the second argument as the escape character. This is of
> course not the utmost of micro efficiency, but I doubt it would matter
> much.)
>
> But I don't have in depth knowledge of the Postgres SQL parser and
> evaluator so I may be way off base.

That is also an excellent idea. Just convert their escape to \ inside
the parser. Of course, they still have to use \\ to get a \, as in any
string. Great idea.

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