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From: "vlsi (@vlsi)" <noreply+vlsi@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Wed, 09 Apr 2025 18:39:13 +0000
Subject: Re: [pgjdbc/pgjdbc] PR #3528: Implement performance fix for catalog check in DatabaseMetaData
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I think it should be uncommon for the client code to ask for a list of "procedures in a foreign catalog", so it should be fine to go with `and false` trick.
At the same time, certain cases make it easy to return empty resultset without making a database roundtrip.

@SophiahHo , in some of the cases, we use `org.postgresql.core.BaseStatement#createDriverResultSet(Field[] fields, List<Tuple> tuples)` can create resultset. For instance, `getProcedureColumns` prepares `Field[]` declaration, and then it executes a query.
In that case we could use something like

```java
if (catalog != null && !catalog.equals(...)) {
  // Returns empty resultset
  ((BaseStatement) createMetaDataStatement()).createDriverResultSet(f, v)
}
```

I guess Dave meant something like that. WDYT?