Search Postgresql Archives

Re: How are foreign key constraints built?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sun, Jan 23, 2005 at 03:19:10PM -0600, Jim C. Nasby wrote:

> > People have this weird notion that an index-based plan is always faster
> > than anything else.  If you like you can try the operation with "set
> > enable_seqscan = off", but I bet it will take longer.
> 
> Well, every other database I've used can do index covering, which means
> index scans *are* faster.

... on those database systems.  Indexes are different in Postgres in
general: they don't have visibility info (other systems don't need it,
tuples are always visible), and in some databases you have clustered
indexes, where the index is also the heap.

-- 
Alvaro Herrera (<alvherre[@]dcc.uchile.cl>)
"We are who we choose to be", sang the goldfinch
when the sun is high (Sandman)

---------------------------(end of broadcast)---------------------------
TIP 4: Don't 'kill -9' the postmaster

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux