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On limiting selection

Posted by admin (Graham Ellis), 5 September 2002
Chances are that if you're selecting within an application, you want to receive back and work on all the rows that match. If you're using the mysql client though, you might want to see just a few lines of your result set. You can add a limit clause onto the end of your select command, for example:

     LIMIT 5,10

which will give you ten rows back starting at matching row number five.

Notes:

* The first matching row is numbered 0 not 1.
* The second parameter is the number of rows you want, and not the number of the last row you want.
* If the table is updated between two limited selects to give you everything between them, you might not get every match back and/or you may get some duplicates.
* It's not a problem if you ask for more rows than are available.
* If you give a single parameter, you get that many matched rows from the first match (match 0)


Posted by admin (Graham Ellis), 4 August 2003
An additional note -
        LIMIT 0
will always return an empty set, and do so quickly.  It's a useful way to check your query and to get the column types of the results under certain APIs



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