A conditional DROP TABLE function - Mailing list pgsql-general

Hi All,

Here's a Conditional drop_table func for those interested.  There was a
thread on this a long time back.

We do this all the time :

  DELETE TABLE sales;
  CREATE TABLE sales (...);

But nobody likes

  ERROR:  table "sales" does not exist

which we see all the time in the logs.  I want to show the logs to none
db folk -- so we can't have those error messages in it.

(There must be some explaination why postgresql (and Oracle as well) do
not have CREATE OR REPLACE TABLE as it does for VIEWs, and FUNCTIONs.
Anybody know?)

Anyway here's drop_table ():


CREATE or REPLACE function drop_table (varchar) returns varchar as '
DECLARE
    tablename  alias for $1;
    cnt        int4;
BEGIN
    SELECT into cnt count(*) from pg_class where relname =
tablename::name;
    if cnt > 0 then
        execute \'DROP TABLE \' || tablename;
        return tablename || \' DROPPED\';
    end if;
    return tablename || \' does not exist\';
END;'
language 'plpgsql' ;


And here's it's usage in an SQL script:

    \set QUIET
    \pset format unaligned
    \pset tuples_only
    \unset QUIET

    select drop_table('sale');
        CREATE TABLE sale ( ... );

Regards, DAvid


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