Re: enum bug

Melvin Davidson wrote:

> Enums are evil!
> http://www.lornajane.net/posts/2010/is-enum-evil

???

This post is about MySQL's enums, which aren't really related to
Postgres enums:

"In order to change the allowed values of an enum column, we
need to issue an alter table statement [...] Alter table
actually creates a new table matching the new structure, copies
all the data across, and then renames the new table to the right
name."

This is not at all how things happen in Postgres' enums.

> enums are from before there were foreign keys

In Postgres, ENUMs are pretty recent actually -- a lot newer than FKs:

commit 57690c6803525f879fe96920a05e979ece073e71
Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
AuthorDate: Mon Apr 2 03:49:42 2007 +0000
CommitDate: Mon Apr 2 03:49:42 2007 +0000

Support enum data types. Along the way, use macros for the values of
pg_type.typtype whereever practical. Tom Dunstan, with some kibitzing
from Tom Lane.

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Álvaro Herrera http://www.2ndQuadrant.com/
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