Re: Terribly slow query with very good plan?

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In the fast case the 'Felhasználók%' part is known at query planning
time, so it can be a prefix search.

In the slow case, the planner doesn't know what that value will be, it
could be something that starts with '%' for example.


First of all, it CANNOT start with '%'. This is a fact and this fact can be determined by analyzing the query. Something that the query planner should do, right?

Second argument: the same query is also slow with the ^@ operator...

Oh I see, the query planner does not know that there will be no % characters in file and folder names.

But what is the solution then? It just seems wrong that I can speed up a query 1000 times by replacing it with a nested loop in a pl/sql function :(

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