RE: [PHP] MySQL performance question

I think, these are identical, because, id column is a primary key and primary keys are unique (and indexed as such). Sincerely, Maxim Maletsky PHP Beginner www.phpbeginner.com > -----Original Message----- > From: Lars Olsson [mailto:lasso@lassoweb.nu] > Sent: Sunday, August 04, 2002 10:28 PM > To: php-general@lists.php.net > Subject: [PHP] MySQL performance question > > Hi all! > > Sorry for being slightly off topic, but this list seems to have it's > fair share of MySQL gurus... :-) Anyway, here's my question: > > Suppose I create a table (called table1) which has a field with only > unique values (called id). Now suppose this table has some rows and that > I want to select ONE of them. I usually do this: > > "SELECT * FROM table1 WHERE id=somevalue" > > Since id is a unique value this can only return (at most) 1 row. Now > let's try this: > > "SELECT * FROM table1 WHERE id=somevalue LIMIT 1" > > This query will produce exactly the same result as the first query. But > which one (if any) of the two queries are the most efficient? Is it > > a) The first one, since it's a less complicated SQL query (less time to > parse) > b) The second one, since it will restrict MySQL from searching further > whenever a row is found > > Any opinions? > > /lasso (lasso@lassoweb.nu) > > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php