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https://issues.apache.org/jira/browse/OFBIZ-5534?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14044784#comment-14044784
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Adam Heath commented on OFBIZ-5534:
-----------------------------------

Well, to do what you would need, would be rather difficult(I think).  Here's 
what would have to happen.

* Allow any pre-existing cached results to be returned.
* Allow new values to be stored into the cache.
* Any values modified during a transaction place a 'whiteout' entry
* Whiteout entries will prevent reading of cached items that match.
* Whiteout entries will prevent storing of items that match into the cache.
* Whiteout entries will clear the cache at the end of the transaction.

Altho, maybe not so difficult.  The changes I have I did entirely last night.


> 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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