Kumar,
pg_class.relname is type "name". You are trying to compare it to p_tablename
which is type "varchar". Try changing your function definition to:
CREATE OR REPLACE FUNCTION public.desc_table(name)
^^^^
HTH
George
SNIP
> CREATE OR REPLACE FUNCTION public.desc_table(varchar)
> RETURNS refcursor AS
> 'DECLARE
>
> ref REFCURSOR ;
> p_tablename ALIAS FOR $1;
>
> BEGIN
> OPEN ref FOR
> SELECT a.attname,
> format_type(a.atttypid, a.atttypmod),
> a.attnotnull,
> a.atthasdef,
> a.attnum
> FROM pg_class c, pg_attribute a
> WHERE c.relname = p_tablename
> AND a.attnum > 0
> AND a.attrelid = c.oid
> ORDER BY a.attnum;
>
> RETURN ref;
> END;'
> LANGUAGE 'plpgsql' VOLATILE;
>
>
> While trying to execute this
> select desc_table('companies');
>
> I got the following error.
> WARNING: Error occurred while executing PL/pgSQL function desc_table
> WARNING: line 7 at open
>
> ERROR: Unable to identify an operator '=' for types 'name' and 'character
> varying'
> You will have to retype this query using an explicit cast
>
SNIP
