RE: [HACKERS] Re: ALTER TABLE DROP COLUMN

Don Baccus <dhogaza@pacifier.com>

From: Don Baccus <dhogaza@pacifier.com>
To: "Hiroshi Inoue" <Inoue@tpf.co.jp>, "Tom Lane" <tgl@sss.pgh.pa.us>
Cc: "PostgreSQL Development" <pgsql-hackers@postgreSQL.org>
Date: 2000-02-28T05:26:30Z
Lists: pgsql-hackers
At 12:21 PM 2/28/00 +0900, Hiroshi Inoue wrote:

>My idea is essentially an invisible column implementation.
>DROP COLUMN would change the target pg_attribute tuple
>as follows..

I don't see such a solution as being mutually exclusive with
the other one on the table.

Remember ... Oracle provides both.  I suspect that they did so
because they were under customer pressure to provide a "real"
column drop and a "fast" (and non-2x tablesize!) solution.  So
they did both.  Also keep in mind that being able to drop a
column in Oracle is a year 1999 feature ... and both are provided.
More evidence of pressure from two points of view.

Of course, PG suffers because the "real" column drop is a 2x
space solution, so the "invisibility" approach may more frequently
be desired.

Still... as time goes on and PG gets adopted by more and more 
serious, large-scale users (which we all are working towards, 
right?) I suspect that each camp will want to be served.




- Don Baccus, Portland OR <dhogaza@pacifier.com>
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