I have an application I'm developing with PHP & Firebird.  While it mostly works fine - I've been having what I believe to be transaction issues.

 

One problem was visibility - committed changes were not visible to selects.  I know they were committed - after executing the commit within the scripts, I could see the changes within FlameRobin.  Yet the script didn't see them.

 

I also saw the "oldest active transaction" getting old...and it didn't seem to update until I killed some of the longer-running php processes.

 

I use explicit transactions for every insert or update followed by explicit commits.  Could my problem be that I need to use explicit transactions for the selects as well?

Quite likely. If you have a long running PHP process which does lots of selects and never does a commit it'll quite likely all be in one transaction which can produce the symptoms you describe.

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Tim Ward