RE: Add partial :-variable expansion to psql \copy

Always better with a file attached :-/

Sorry for the noise.

--
Fabien.
________________________________
De : Fabien COELHO <coelho(at)cri(dot)ensmp(dot)fr>
Envoyé : lundi 31 mars 2025 13:48
À : PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Objet : Add partial :-variable expansion to psql \copy

Hello,

I've been biten by psql's \copy lack of variable expansion, in a limited-access docker-inside-VM context where COPY is not a viable option and hardwired names are not desirable. The attached patch allows \copy to use variable's values in place of table and file names:

```psql
\set table 'some table'
\set input 'some file name.csv'
\copy :"table" from :'input' with (format csv)
```

--
Fabien.