Thread

1. Create Primary Key?

   Webb Sprague <wsprague100@yahoo.com> — 2000-08-30T00:37:14Z

   Apropos of my last question:
   
   Is there syntax to create a primary key after the
   table has been defined and populated?  I think I could
   speed things up quite a bit by not having any indexes
   at all when I do my mass copies.
   
   Thanks, and my apologies if that is a totally stupid
   question.
   
   W
   
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2. Re: Create Primary Key?

   Stephan Szabo <sszabo@megazone23.bigpanda.com> — 2000-08-30T01:10:23Z

   We don't currently support the SQL syntax for adding
   a PK to a table.  However, if you have the columns
   as NOT NULL already, adding a unique index to the
   columns in question has the same general effect.
   
   Stephan Szabo
   sszabo@bigpanda.com
   
   On Tue, 29 Aug 2000, Webb Sprague wrote:
   
   > Apropos of my last question:
   > 
   > Is there syntax to create a primary key after the
   > table has been defined and populated?  I think I could
   > speed things up quite a bit by not having any indexes
   > at all when I do my mass copies.
   
   
   

3. Re: Create Primary Key?

   Jie Liang <jliang@ipinc.com> — 2000-08-30T01:50:53Z

   Hi,
   
   It suppose to use ALTER TABLE tablename ADD constraint xxx primary
   key(columnname),
   unforturatly, Pg7.0 still haven't implemented it yet, so except foreign
   key ,other constarints,
   you have to choose:
   1. rename your old table, recreate an new one with primary key, then use
   
   insert into newtable select * from oldtable.
   2. use pg_dump -t tablename -f scriptfile dbname
   in shell , edit that scriptfile, add primary key there,
   drop your table, then reload it again:
   psql dbname<scriptfile
   
   Webb Sprague wrote:
   
   > Apropos of my last question:
   >
   > Is there syntax to create a primary key after the
   > table has been defined and populated?  I think I could
   > speed things up quite a bit by not having any indexes
   > at all when I do my mass copies.
   >
   > Thanks, and my apologies if that is a totally stupid
   > question.
   >
   > W
   >
   > __________________________________________________
   > Do You Yahoo!?
   > Yahoo! Mail - Free email you can access from anywhere!
   > http://mail.yahoo.com/
   
   --
   Jie LIANG
   
   Internet Products Inc.
   
   10350 Science Center Drive
   Suite 100, San Diego, CA 92121
   Office:(858)320-4873
   
   jliang@ipinc.com
   www.ipinc.com
   
   
   
   
   

4. Re: Create Primary Key?

   D'Arcy J.M. Cain <darcy@druid.net> — 2000-08-30T11:42:48Z

   Thus spake Stephan Szabo
   > We don't currently support the SQL syntax for adding
   > a PK to a table.  However, if you have the columns
   > as NOT NULL already, adding a unique index to the
   > columns in question has the same general effect.
   
   Except for interfaces such as PyGreSQL that recognize the primary key
   and use it.
   
   > > Is there syntax to create a primary key after the
   > > table has been defined and populated?  I think I could
   > > speed things up quite a bit by not having any indexes
   > > at all when I do my mass copies.
   
   Why not just use the copy function?  That's what it's for.
   
   -- 
   D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
   http://www.druid.net/darcy/                |  and a sheep voting on
   +1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.
   
   

5. Re: Create Primary Key?

   Stephan Szabo <sszabo@megazone23.bigpanda.com> — 2000-08-30T14:52:07Z

   On Wed, 30 Aug 2000, D'Arcy J.M. Cain wrote:
   
   > Thus spake Stephan Szabo
   > > We don't currently support the SQL syntax for adding
   > > a PK to a table.  However, if you have the columns
   > > as NOT NULL already, adding a unique index to the
   > > columns in question has the same general effect.
   > 
   > Except for interfaces such as PyGreSQL that recognize the primary key
   > and use it.
   
   True.  You'd have to see what it was doing to determine the primary key
   and try to do the same things.