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What are you doing when the error occurs?
There is a stored procedure which truncates a table and the truncate fails with this error. The question is if this error can appear when someone else is trying to make a simple select from that table. The table has no constraint.
The TRUNCATE command is a DDL operation. It requires an exclusive lock before it can proceed. Sometimes, a session will wait for the holder of the lock to release it and then that session will acquire the lock and proceed. In this case, the TRUNCATE command is not willing to wait around for the older to release the lock. So the command aborts.