Re: [HACKERS] BUG #1883: Renaming a schema leaves inconsistent

With the following errors caused by ALTER SCHEMA RENAME, I recommend we
remove this feature for 8.1 and revisit it for 8.2. I would just remove
the grammar construct for it and the documentation.

To fix this, we would need to redesign the way we store DEFAULT sequence
assignments, and I don't think that is a good thing to do during beta.
I see people wanting bitmapped scans ASAP, not renaming of schemas. Our
beta time is better spent on other things than getting this to work now.

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Bruce Momjian wrote:
> Tom Lane wrote:
> > Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > > This item has been added to the 8.1 bugs list:
> > > http://momjian.postgresql.org/cgi-bin/pgbugs
> >
> > This isn't going to be fixed for 8.1. I think it's really a variant of
> > the TODO item
> > o %Have ALTER TABLE RENAME rename SERIAL sequence names
>
> Well, it might be a variant, but its failure is much worse. For a table
> rename, you just get a strange \d display:
>
> test=> CREATE TABLE test (x SERIAL);
> NOTICE: CREATE TABLE will create implicit sequence "test_x_seq" for serial column "test.x"
> CREATE TABLE
> test=> ALTER TABLE test RENAME TO test2;
> ALTER TABLE
> test=> INSERT INTO test2 VALUES (DEFAULT);
> INSERT 0 1
> test=> \d test2
> Table "public.test2"
> Column | Type | Modifiers
> --------+---------+-----------------------------------------------------
> x | integer | not null default nextval('public.test_x_seq'::text)
>
> The insert into the table still works. For the schema rename, the
> insert into the table doesn't work anymore. The odds that a schema
> rename is going to have _no_ sequence dependencies in the same schema
> seems pretty unlikely, meaning rename schema is almost guarantted to
> create some broken table defaults. With this behavior, if we can't fix
> it in 8.1, I am wonderingf we should just disable the feature:
>
> test=> CREATE SCHEMA aa;
> CREATE SCHEMA
> test=> CREATE TABLE aa.test (x SERIAL);
> NOTICE: CREATE TABLE will create implicit sequence "test_x_seq" for serial column "test.x"
> CREATE TABLE
> test=> ALTER SCHEMA aa RENAME TO bb;
> ALTER SCHEMA
> test=> INSERT INTO bb.test VALUES (DEFAULT);
> ERROR: SCHEMA "aa" does NOT exist
> test=> \d bb.test
> Table "bb.test"
> Column | Type | Modifiers
> --------+---------+-------------------------------------------------
> x | integer | not null default nextval('aa.test_x_seq'::text)
>
> --
> Bruce Momjian | http://candle.pha.pa.us
> pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
> + If your life is a hard drive, | 13 Roberts Road
> + Christ can be your backup. | Newtown Square, Pennsylvania 19073
>
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>

--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073