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Hi all,
I have an SQL problem. I have a query like this
select 
myfunction(field1) from mytable where field2 like 'A%'
The table mytable 
is really big, the selection like 'A%' extracts quickly 
only a few records, 
while myFunction is a bit slow
A "good" execution plan should extract records 
and apply myFuntion to the 
results, but the system applies myFunction to the 
whole table, and then it 
does the filter...it takes forever....
I 
tried to rewrite my query this way:
with x as (select field1 from mytable 
where field2 like 'A%')
select myfunction(field1) from x
but it's 
still very slow!
Can you help 
me?
Bye
Franco
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
http://www.francolombardo.net
Scala, 
Java, As400.....
http://twitter.com/f_lombardo
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 		 	   		   		 	   		  
 
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