Re: ALTER TABLE modifications - Mailing list pgsql-patches

From Peter Eisentraut
Subject Re: ALTER TABLE modifications
Date
Msg-id Pine.LNX.4.44.0311121959560.32472-100000@peter.localdomain
Whole thread Raw
In response to ALTER TABLE modifications  (Rod Taylor <pg@rbt.ca>)
Responses Re: ALTER TABLE modifications
Re: ALTER TABLE modifications
List pgsql-patches
Rod Taylor writes:

> ALTER TABLE tab ADD COLUMN col DEFAULT 3, ADD CHECK (anothercol > 3);
>         The above combinational syntax is commented out in gram.y. The
>         support framework is used in both the above and below items, but
>         arbitrary statements probably have some issues -- I've not
>         tested enough to determine.
>
>         If it is useful, it will be submitted at a later date.

I think it's perfectly fine to write two separate ALTER TABLE statements.
No need to introduce this nonstandard syntax.

> ALTER TABLE tab ALTER COLUMN col TYPE text TRANSFORM ...;
>         Currently migrates indexes, check constraints, defaults, and the
>         column definition to the new type with optional transform. If
>         the tranform is not supplied, a standard assignment cast is
>         attempted.

Please don't use the term "transform".  It is used by the SQL standard for
other purposes.  What kind of object would you put in place of the "..."
anyway?  A function?  What syntax do other databases use?

--
Peter Eisentraut   peter_e@gmx.net


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