How to optimize JDBC on SELECT ... From table1 WHERE ... OR ... OR ... OR .

Hi,
I've been given a java.util.Collection of data (actually composite alternative keys) to query Oracle. so I need to build dynamic SQL query:
SELECT ... FROM table1
WHERE (ak_col1 = ... AND ak_col2 = ...)
OR (ak_col1 = ... AND ak_col2 = ...)
OR (ak_col1 = ... AND ak_col2 = ...)
... // till the last element in the Collection
The size of Collection is between 100 to 500. When I construct this query as String and passed to JDBC Statment. It can take a few seconds to run.
I wonder if any one know a better way to imporve the performance?
TIA
chuck

It might be perform better and it would certainly maintain performance whether 100 or 500 entries existed if you could transform the sql logic to use the between keyword. No idea if the data would support this, and you would have to preprocess the Collection (which may negate any overall performance benefit). It may not completely eliminate the OR condition, but it could minimize the count. Something like (This solution is totally data dependent.):
SELECT ... FROM table1
WHERE (ak_col1 between ... and .... and ak_col2 between ... and ...)
or (ak_col1 between ... and .... and ak_col2 between ... and ...)================
It might be easier, and is not as data dependent to try using an inlist. Perhaps something like this:
SELECT ... FROM table1
WHERE (ak_col1 in (...,...,...,...) and ak_col2 in (...,...,...,...) )
or (ak_col1 in (...,...,...,...) and ak_col2 in (...,...,...,...))Once again, you would have to preprocess the Collection to build this SQL which could negate any overall performance benefit. And you would be minimizing the but not eliminating the OR conditions. This is not as as good a solution from a performance perspective as using the between.
I kind of like the previous posters idea of looking at the table structures and modifying them to eliminate the need for multiple OR conditions. As stated, that's not always possible.
In most cases, when Oracle is provided this type of SQL (500 OR's, 1000 AND's) the optimizer simply gives up and scans the table. You are correct in looking at alternative strategies unless this is a very small table and scanning the table is a reasonable thing to do.
There are probably a handful of other possible strategies for altering the SQL to attempt to improve or stabilize performance.
Just ramblings... Not really a Java question... Good luck though.

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How to optimize JDBC on SELECT ... From table1 WHERE ... OR ... OR ... OR .

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