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https://issues.apache.org/jira/browse/OFBIZ-5534?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14044840#comment-14044840
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Adrian Crum commented on OFBIZ-5534:
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There is a flaw in my plan: Code might try to read/find an updated value, and
it will get the original/unmodified value from the cache instead of the updated
value. Maybe cache reads should go to the transaction manager as well. The tx
mgr looks in its list of pending changes, and if the entity value isn't in the
list, it delegates to the delegator.
It is an interesting problem to solve. I think it will require changing how
transactions are handled, instead of re-engineering the cache.
> Dirty reads from entity cache
> -----------------------------
>
> Key: OFBIZ-5534
> URL: https://issues.apache.org/jira/browse/OFBIZ-5534
> Project: OFBiz
> Issue Type: Bug
> Components: framework
> Affects Versions: Release Branch 11.04, SVN trunk, Release Branch 12.04,
> Release Branch 13.07
> Reporter: Jacopo Cappellato
> Assignee: Adam Heath
> Attachments: unittest-dirtyreadsfromcache.patch
>
>
> Even if database transaction isolation level is set to "ReadCommitted", a
> transaction can get uncommitted records from the entity cache, under certain
> circumstances.
> Here is a test case:
> 1) transaction T1 creates a record
> 2) T1 calls findOne to retrieve it: the read will be successful (because T1
> can read data generated in T1 even if not committed) and the record will be
> added to the cache
> 3) T1 calls another service with requireNewTransaction set to true: this will
> run the second service in a new transaction T2
> 4) T2 calls findOne to retrieve the record created by T1: if useCache is set
> to false it should fail; if useCache is set to true it will succeed (getting
> the record from cache, even if the data is not committed to the db)
> The result in #4 is wrong because T2 should not see the uncommitted record
> We should never add uncommitted records to the entity cache.
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