If it's a bash script you could use:
#####
SomeTable=<Table you're about to create>
TableTest=$(psql -d <your new db> -U <its owner> -ntc "select relname from
pg_class where relname='$SomeTable'")
[[ -n "$TableTest" ]] && psql -d <your new db> -U <its owner> -nc "drop
table $SomeTable"
#####
It's not quite "in postgres's sql", but it could get the job done
>-----Original Message-----
>From: Sam Carleton [mailto:ehc@linux-info.net]
>Sent: Saturday, October 18, 2003 22:37
>To: pgsql-admin@postgresql.org
>Subject: [ADMIN] sql scripts
>
>
>I am new to postgres and your mailing lists, please let me know if I
>am posting in the wrong list.
>
>I am working on creating my first database in Postgres. In the
>script that will create all the tables for the firs time, I would
>like to have a conditional statement to delete a table, if it
>already exists. I know the other databases create such a condtional
>statement for you when you export the schema. What would such a
>conditional statement look like in Postgres's sql?
>
>sam
>
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