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Lets assume that i need to execute a spring batch job with 2 steps.step 1 is to read data from a postgres table and update values in the same table. step 2 is to read data from another postgres table and update this table. How can i achieve transactions at job level for this scenario?

That is, if the second step fails, then the first step should be rolled back.

Varadharajan Mukundan
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3 Answers3

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Have you considered using job-level transactionality?

Job level Transactionality in Spring Batch

It's important to consider the potential volume size you are managing, in order to avoid out-of-the-limit commits or rollbacks.

Community
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mantoviejo
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i'm not sure if there even exists an solution with automatic chained/multi-level transaction handling that works reliable (or does not need a lot resources on database side)

if the second step fails, then the first step should be rolled back

well you could combine both steps into one:

  • read from first table A
  • use processor to update table A
  • use processor to read from table B
  • use writer to update table B

the performance will suffer a lot, because the read on table B will be a single read vs the cursor based for table a

i would go with a compensating strategy like this

  • (optional) tables in use are temporary tables and not the real "production" tables, makes it easier to work with compensating with decoupling the datastores from the production
  • a failed step 1 triggers another step or another job/script
  • this step/job/script deletes as necessary (rows or complete table)
Michael Pralow
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  • is it possible to have multiple tasklets or chunks inside a single step? if it is, then can we represent the above two tasks as 2 tasklets under a single step, which can be controlled by a transaction manager. – Varadharajan Mukundan Jan 11 '12 at 14:42
  • a Tasklet is a simplified Step and a Step is a domain object that encapsulates an independent, sequential phase of a batch job http://static.springsource.org/spring-batch/reference/html/domain.html#domainStep – Michael Pralow Jan 11 '12 at 20:44
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Put a BEGIN statement before Step 1 and a COMMIT statement after Step 2.

Kouber Saparev
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  • that is not how spring batch works with transaction, the transaction demarcation happens at unit of work level (aka commit-rate), steps are above this level – Michael Pralow Jan 11 '12 at 11:28