You are correct... my apologies, I was thinking in VB where I built a handler to let me sent multiple sql statements in one chunk and where the '@' doesn't matter.
BB -----Original Message----- From: Paul DuBois [mailto:[EMAIL PROTECTED]] Sent: Monday, January 28, 2002 11:28 AM To: [EMAIL PROTECTED]; Richard Morton; DL Neil; [EMAIL PROTECTED] Subject: RE: Selecting the row with largest number in a column At 10:06 -0500 1/28/02, Butch Bean wrote: >Richard, > >I use this with all kinds of situations. >I am using this function and others like it on tables with 100k to 3m >records. >They always work best when the field your looking for info on is indexed. >Order By only causes a second process that seems unnecessary but I have not >tested it directly > >Keep in mind that when I do use max() I am only interested in the highest >number, I don't care how many are the highest or what they are. But... > >This will get you all or the record you are looking for using MySQL >variables(I think someone else had this answer posted as well): > >SELECT @maxage:=max(age) from contacts; >SELECT * FROM contacts WHERE age=@maxage; > >The above can be one call > >Perl Example: > >my $getbigage = $dbh->prepare( > "SELECT @maxage:=max(age) from contacts;". > "SELECT * FROM contacts WHERE age=@maxage;"; I don't believe this will work. @ in double-quoted Perl strings must be escaped with a backslash. More important, you cannot issue multiple queries at a time. In the case above, the MySQL will return an error indicating a syntax error at the semicolon that occurs within the string. >. >. >$getbigage->execute(); >...$getbigage->fetchrow_array()... >. > >I use VB and Perl and the examples I could give you can get lengthy > >This example would be very slow in comparison >> SELECT * >> FROM contacts >> ORDER BY age DESC >> LIMIT 1 > >Butch Bean --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
