performance left outer join very poor 1

[hos2]

I changed a query from an equal join to a left outer join but then the performance is suddenly 10 times as slow ??

Is this normal or do I miss something ??

old code

$query1="SELECT * FROM ";
	$query1=$query1 . "clienttable,contacttable AS co1 WHERE co1.coclid=clid ";
	$query1=$query1 . " AND clname like '$alfabetisch%' ";
	$query1=$query1 . " order by $o";

new code

$query1="SELECT * FROM ";
	$query1=$query1 . "clienttable left outer join contacttable AS co1 ON co1.coclid=clid WHERE ";
	$query1=$query1 . " clname like '$alfabetisch%' ";
	$query1=$query1 . " order by $o";

I only have a few thousand records but still I have to wait for 30 seconds with the left outer join

 

[r937]

what table is the clname column in?

rudy | r937.com | Ask the Expert | Premium SQL Articles
SQL for Database-Driven Web Sites (next course starts May 8 2005)

 

[hos2]

clname is from the clienttable

 

[r937]

your query is okay

sorry, i do not know why it's taking longer

do you have indexes on co1.coclid and clid?



rudy | r937.com | Ask the Expert | Premium SQL Articles
SQL for Database-Driven Web Sites (next course starts May 8 2005)

 

[hos2]

OK the index did the trick bu I still find it fuzzy that it had was so slow by just altering it to a left outer join