If one is seeing waits for enq: TX – row lock contention  then there could be a lot of reasons. One distinguishing factor is the lock mode. If the lock mode is exclusive (mode 6) then it’s most likely a classic row lock where two sessions are trying to modify the same row. On the other hand if the lock mode is share (mode 4)  it’s typically going to be Primary/Unique Key: inserting a unique key when  someone else has already inserted that key but not committed Foreign Key: Inserting a foreign when then parent value has been inserted but not…