Re: Having trouble passing a shell variable to a query from psql command line

On Fri, Aug 29, 2025 at 1:52 PM Murthy Nunna <mnunna(at)fnal(dot)gov> wrote:

> Hello,
>
>
>
> Below works:
>
>
>
> psql -d mydb -t -A -c "SELECT relkind FROM pg_class WHERE relname =
> 'pg_trigger' ;"
>
> r
>
>
>
> I am getting syntax error from following:
>
>
>
> echo $SHELL_VAR
>
> pg_trigger
>
>
>
> psql -d mydb -t -A -c "SELECT relkind FROM pg_class WHERE relname =
> :'SHELL_VAR' ;" -v SHELL_VAR="$SHELL_VAR"
>
> ERROR: syntax error at or near ":"
>
> LINE 1: SELECT relkind FROM pg_class WHERE relname = :'SHELL_VAR' ;
>
> ^
>
> Is psql script necessary to pass shell variable?
>

Yeah. From the cli KISS and do regular bash variable string expansion.

psql -d mydb -tAc "SELECT relkind FROM pg_class WHERE relname =
${SHELL_VAR} ;"

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