Re: Useless "Replica Identity: NOTHING" noise from psql \d

On Wed, Mar 26, 2014 at 12:20:07PM -0300, Alvaro Herrera wrote:
> Bruce Momjian wrote:
> > On Mon, Mar 24, 2014 at 09:07:07PM -0400, Bruce Momjian wrote:
> > > > In the "INDEX" case, should the output mention specifically which index
> > > > is being considered?
> > > 
> > > Ah, good idea.  Updated patch attached.  The output is now:
> > > 
> > >     test=> \d+ test
> > >                              Table "public.test"
> > >      Column |  Type   | Modifiers | Storage | Stats target | Description
> > >     --------+---------+-----------+---------+--------------+-------------
> > >      x      | integer | not null  | plain   |              |
> > >     Indexes:
> > >         "test_pkey" PRIMARY KEY, btree (x) REPLICA IDENTITY
> > >         "i_test2" btree (x)
> > > -->    Replica Identity: USING INDEX "test_pkey"
> > >     Has OIDs: no
> > > 
> > > However, now that I look at it, it seems redundant as REPLICA IDENTITY
> > > is already marked on the actual index.  Ideas?
> > 
> > Hearing nothing, I have gone back to the previous patch that just marks
> > replica identity as USING INDEX;  applied patch attached.
> 
> Not opposed to this, but it seems a bit strange; REPLICA IDENTITY is a
> property of the table, not of any individual index.  I think we should
> lose the token in the "Indexes" section.

That is an interesting idea.  It would mean that \d table would not show
anything about replica identity, because right now it does:
test=> \d test     Table "public.test" Column |  Type   | Modifiers--------+---------+----------- x      | integer |
notnullIndexes:    "test_pkey" PRIMARY KEY, btree (x) REPLICA IDENTITY
 

That seems logical.  So under the new plan, \d would show:
test=> \d test     Table "public.test" Column |  Type   | Modifiers--------+---------+----------- x      | integer |
notnullIndexes:    "test_pkey" PRIMARY KEY, btree (x)
 

and \d+ would show:
    test=> \d+ test                             Table "public.test"     Column |  Type   | Modifiers | Storage | Stats
target| Description    --------+---------+-----------+---------+--------------+-------------     x      | integer | not
null | plain   |              |    Indexes:        "test_pkey" PRIMARY KEY, btree (x)Replica Identity: USING INDEX
"test_pkey"   Has OIDs: no
 

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
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