Re: BUG #15198: nextval() accepts tables/indexes when adding adefault to a column

On 5/16/18 05:29, PG Bug reporting form wrote:
> bugtest=# CREATE TABLE demo(i int default nextval('demo') PRIMARY KEY);
> CREATE TABLE
> bugtest=# ALTER TABLE demo ADD COLUMN j int default nextval('demo_pkey');
> ALTER TABLE
> bugtest=# \d demo
>                            Table "public.demo"
>  Column |  Type   | Collation | Nullable |            Default
> --------+---------+-----------+----------+--------------------------------
>  i      | integer |           | not null | nextval('demo'::regclass)
>  j      | integer |           |          | nextval('demo_pkey'::regclass)
> Indexes:
>     "demo_pkey" PRIMARY KEY, btree (i)
> 
> bugtest=# INSERT INTO demo (i, j) VALUES (1,1);
> INSERT 0 1
> bugtest=# INSERT INTO demo (i, j) VALUES (DEFAULT, DEFAULT);
> ERROR:  42809: "demo" is not a sequence
> LOCATION:  init_sequence, sequence.c:1139

You are right that this is not optimal behavior.  I'm not sure if it's
worth fixing, however.  (Introduce a regsequence type to use in place of
regclass?)

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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