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https://issues.apache.org/jira/browse/DERBY-7042?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16812632#comment-16812632
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Michael Schuetze commented on DERBY-7042:
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{quote}I am trying to understand how to trip this bug, but so far I have not
been able to make it occur. It runs without error for me.{quote}
After reading the comment chain, it seems you have figured it out. If you have
any more questions feel free to let me know.
The actions are performed correctly, the timing for how long the actions take
is what is wrong.
> Multiple triggers with rowLocking = false causes deadlock
> ---------------------------------------------------------
>
> Key: DERBY-7042
> URL: https://issues.apache.org/jira/browse/DERBY-7042
> Project: Derby
> Issue Type: Bug
> Components: Documentation, JDBC
> Affects Versions: 10.8.2.2, 10.8.3.0, 10.9.1.0, 10.10.1.1, 10.10.2.0,
> 10.11.1.1, 10.12.1.1, 10.13.1.1, 10.14.1.0, 10.14.2.0, 10.15.1.3
> Environment: ------------------ Java Information ------------------
> Java Version: 1.8.0_201
> Java Vendor: Oracle Corporation
> OS name: Linux
> OS architecture: i386
> OS version: 4.15.0-46-generic
> java.specification.name: Java Platform API Specification
> java.specification.version: 1.8
> java.runtime.version: 1.8.0_201-b09
> --------- Derby Information --------
> [.../TriggerRepro/derby/derby-10.14.1.0.jar] 10.14.1.0 - (1808820)
> Reporter: Michael Schuetze
> Priority: Minor
> Labels: documentation, performance
> Attachments: Derby7042.java, Derby7042.java
>
>
> Repro for the bug can be found here:
> [https://github.com/mjschuetze102/TriggerRepro]
> Includes a detailed README of steps that show effect of bug as well as two
> versions of the Derby database. 10.8.1.2, the last version where the bug was
> not present and version 10.14.1.0, for easy access.
> This may just be an issue of not having enough documentation on database
> Triggers (see Conclusions Based on Results)
> h2. Summary of Issue
> *Having multiple triggers with {{'derby.storage.rowLocking', 'false'}} causes
> issues with deadlocking*
> # Executing Update trigger causes deadlock when there is an Insert or Delete
> trigger
> # Executing Insert trigger causes deadlock when there is a Delete trigger
> # Executing Delete trigger does not cause deadlock
> *{{'derby.locks.deadlockTimeout'}} does not seem to work in above case*
> # While executing issue above, none of the triggers were terminated and
> waitTimeout time was hit
> h2. Conclusions Based on Results
> *Having multiple triggers with {{'derby.storage.rowLocking', 'false'}} causes
> issues with deadlocking*
> Triggers seem to get into deadlock scenarios with any trigger defined after
> itself. If this is the case, it should be documented somewhere that
> rowLocking needs to be enabled to use the trigger feature if multiple
> triggers would be used on the same database table.
> *{{'derby.locks.deadlockTimeout'}} does not seem to work in above case*
> Based on documentation, I could not find any concrete evidence of whether
> this is intended functionality.
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