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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ron Johnson <ronljohnsonjr@gmail.com>
cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
Subject: Re: Having trouble passing a shell variable to a query from psql
 command line
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Comments: In-reply-to Ron Johnson <ronljohnsonjr@gmail.com>
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Ron Johnson <ronljohnsonjr@gmail.com> writes:
> 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} ;"

This isn't a great recommendation because bash is not aware of
SQL's quoting rules.  It'll work in simple cases, but there's
a risk of SQL injection if the value of SHELL_VAR comes from
an untrustworthy source.

			regards, tom lane