What could cause error message Query thread is still in progress

[akaya]

Hello,

We recently set TOracleQuery.Threaded = True for executing a query in background thread. Sometimes we get error message "Query thread is still in progress". What could cause this error?

TOracleQuery.ThreadSynchronized = True
TOracleSession.ThreadSafe = True
DOA 4.1.3.5 - Delphi 10.1 Berlin

Thank you.

 

[akaya]

Checking TOracleQuery.ThreadIsRunning before Execute seems to fix this issue. However, query in question was firing once per minute with execution time of 0.05 seconds. I do not see how it was possible that Thread was still executing.