Re: Converting char to varchar automatically

There really is no easy way to make a single ALTER for each table unless
you use a programming language. However, adding a
GROUP BY c.relname,
a.attname

would certainly simplify editing. Then you can combine all the
ALTER COLUMN's for each table.

On Wed, Oct 8, 2014 at 6:21 PM, Andrus <kobruleht2(at)hot(dot)ee> wrote:

> Hi!
>
> Thank you.
>
> >This revised query should give you what you need:
> >SELECT 'ALTER TABLE ' || quote_ident(n.nspname) || '.'
> > || quote_ident(c.relname)
> > || ' ALTER COLUMN ' || quote_ident(a.attname) || ' TYPE
> varchar(' || i.character_maximum_length || ');'
> > FROM pg_class c
> > JOIN pg_namespace n ON n.oid = c.relnamespace
> > JOIN pg_attribute a ON a.attrelid = c.oid
> > JOIN pg_type t ON t.oid = a.atttypid
> > JOIN information_schema.columns i ON (i.table_name = c.relname AND
> i.column_name = a.attname)
> >WHERE t.typname = 'bpchar'
> > AND c.relkind = 'r'
> > AND n.nspname <> 'pg_catalog' and not attisdropped;
>
> How to create single alter table command for every table ?
> Can we use string concat aggregate function or window functions or plpgsql
> or something other ?
>
> Andrus.
>

--
*Melvin Davidson*
I reserve the right to fantasize. Whether or not you
wish to share my fantasy is entirely up to you.