Update n number of records using JPA with Optimistic locking

Posted by Jacques René Mesrine on Stack Overflow See other posts from Stack Overflow or by Jacques René Mesrine
Published on 2010-05-04T01:49:15Z Indexed on 2010/05/04 1:58 UTC
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Filed under:

jpa

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mysql

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java

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jdbc

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ejb3

I have a table with a column called "count" and I want to run a cron job that will trigger a statement that performs a SQL like this:

update summaryTable set count=4;

Note that there might be concurrent threads reading & changing the value for "count" when this cron job is triggered. The table has a version column to support Optimistic Locking.

What's an efficient way to update the count in JPA ?

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