how to add a new column to system table

xiapw wrote:

I wanted to add a new column to system table(pg_database),but failed
at last. Who know how to do this and can you tell me ?

It is pretty complicated. I would pick an existing column in the table
and find all references to that in the backend, then adjust other values
to match. Actually adding a column to a system table is quite complex
and you might be better off creating a new table that refernces
pg_database and linking to it.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
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""xiapw"" <xiapw@lreis.ac.cn> wrote in message
news:000e01c60c57$52c5f170$4503a8c0@sting...

I wanted to add a new column to system table(pg_database),but failed at
last. Who know how to do this and can you tell me ?

A recent change to pg_database (adding a new column) happened on

--
Sun Jul 31 17:19:21 2005 UTC (4 months, 4 weeks ago) by tgl

Log Message:
-----------
Add per-user and per-database connection limit options.
This patch also includes preliminary update of pg_dumpall for roles.
Petr Jelinek, with review by Bruce Momjian and Tom Lane.
--

Try to find out related changes on pgsql.committers.

Regards,
Qingqing