| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Christopher Kings-Lynne <chris(dot)kings-lynne(at)calorieking(dot)com> |
| Cc: | Dhanaraj(dot)M(at)Sun(dot)COM, Mark Woodward <pgsql(at)mohawksoft(dot)com>, Richard Huxton <dev(at)archonet(dot)com>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Performance Issues |
| Date: | 2006-05-24 04:28:02 |
| Message-ID: | 25494.1148444882@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Christopher Kings-Lynne <chris(dot)kings-lynne(at)calorieking(dot)com> writes:
>> Thank you for your help. I found that an implicit index is created for
>> the primary key in the current version. However, it is not done in 7.x
>> version.
> It absolutely is created in all 7.x versions of PostgreSQL.
And every other version too. PRIMARY KEY/UNIQUE syntax was not
supported before this patch:
1997-12-04 18:07 thomas
* src/backend/parser/: analyze.c, gram.y: Add SQL92-compliant
syntax for constraints. Implement PRIMARY KEY and UNIQUE clauses
using indices.
and in that patch and every subsequent version, unique constraints are
associated with indexes. In fact, we do not even *have* any
implementation method for unique constraints other than the duplicate-
entry-detection code in the btree index AM.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Qingqing Zhou | 2006-05-24 06:16:17 | Re: LIKE, leading percent, bind parameters and indexes |
| Previous Message | Christopher Kings-Lynne | 2006-05-24 04:17:17 | Re: Performance Issues |