You could use EXPLAIN to see if there is a different query plan, but I'd bet there isn't. * will generally be slower, just because you usually won't need EVERY column. If you can specify only certain columns, that will save you some time.
John -----Original Message----- From: sqlite-users-boun...@sqlite.org [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Kristoffer Danielsson Sent: Wednesday, October 28, 2009 12:51 PM To: sqlite-users@sqlite.org Subject: Re: [sqlite] SELECT * vs SELECT columns ? I don't know about SQLite, but in all SQL courses you learn that you should NEVER use the asterisk. The asterisk is merely there to let you quickly view data _manually_. > Date: Wed, 28 Oct 2009 16:02:01 +0200 > From: mi...@limbasan.ro > To: sqlite-users@sqlite.org > Subject: Re: [sqlite] SELECT * vs SELECT columns ? > > I would expect there to be a speed and memory performance *impact* if > the result set contains columns other than the three specified ones, > since obviously the library will need to allocate more memory to hold > the extra data. > > On 10/28/2009 03:52 PM, Pete56 wrote: > > I am searching across two joined tables and am interested in a few > > parameters: > > > > SELECT a.first a.third b.first FROM a JOIN b ON a.RowID = b.RowID WHERE > > value = :value > > > > Is there any speed or memory performance improvement by using SELECT *, > > rather than SELECT<specific columns> ? > > > > If I know there will only be one item (unique :value) selected (LIMIT 1) can > > I make any performance improvements ? > > > > -- > Cu stima, > Mihai Limbasan > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users _________________________________________________________________ Nya Windows 7 - Hitta en dator som passar dig! Mer information. http://windows.microsoft.com/shop _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
