Re: Variable substitution in psql backtick expansion

Fabien COELHO wrote:

> Now it could be decided that \set in psql stays simplistic because it is
> not needed as much as it is with pgbench. Fine with me.

It's not just that. It's that currently, if we do in psql:

\set d sqrt(1 + random(1000) * 17)

then we get that:

\echo :d
sqrt(1+random(1000)*17)

I assume we want to keep that pre-existing behavior of \set in
psql, that is, making a copy of that string and associating a
name to it, whereas I guess pgbench computes a value from it and
stores that value.

Certainly if we want the same sort of evaluator in pgbench and psql
we'd better share the code between them, but I don't think it will be
exposed by the same backslash commands in both programs,
if only for that backward compatibility concern.

Best regards,
--
Daniel Vérité
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