Thanks!!! El día Sunday 07 September 2003 7:59 a Bob Showalter mandó el siguiente correo: > Pablo Fischer wrote: > > Hello! > > > > I have a questionto those lovers of DBI and Databases: which method > > is faster to know the number of rows of a query: > > > > $sth->rows > > > > or > > > > my query but with a COUNT(id) and retrieve the value with: > > > > $query->bind_columns(undef, \$total); > > > > The table its 'big' cause it will manage like 12,000 rows. > > > > In $sth->rows I have this: > > > > SELECT idport FROM ports WHERE port='$portnumber'; > > > > in the bind_columns case I have > > > > SELECT COUNT(idport) FROM ports WHERE port='$portnumber'. > > > > I know that I can test it with EXPLAIN in MySql, however Im testing > > it with 150 records, not with 12,000 (or more) that will be the real > > size of the table. > > The latter should be faster, because the server can do all the counting and > doesn't have to pass each row back to the client for counting. If there's > an index on "port", the count can be determined just by scanning the index, > which could be even quicker. > > In general, you want your queries to return the mininum number of rows > necessary. The second query will always return one row, so that's your best > bet.
-- Pablo Fischer Sandoval ([EMAIL PROTECTED]) http://www.pablo.com.mx http://www.debianmexico.org GPG FingerTip: 3D49 4CB8 8951 F2CA 8131 AF7C D1B9 1FB9 6B11 810C Firma URL: http://www.pablo.com.mx/firmagpg.txt -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
