I have a producer thread in Java pulling items from an Oracle table every n milliseconds.
The current implementation relies on a Java timestamp in order to retrieve data and never re-retrieve them again.
My objective is to get rid of the timestamp pattern and directly update the same items I’m pulling from the database.
Is there a way to SELECT a set of items and UPDATE them at the same time to mark them as “Being processed”?
If not, would a separate UPDATE query relying on the IN clause be a major performance hit?
I tried using a temporary table for that purpose, but I’ve seen that performance was severely affected.
Don’t know if it helps, but the application is using iBatis.
If you are using oracle 10g or higher, you can use the RETURNING clause of the update statement. If you wish the retrieve more than one row you can use the BULK COLLECT statement.
Here is a link to some examples;
http://psoug.org/snippet/UPDATE-with-RETURNING-clause_604.htm