To avoid Mutating trigger there are many ways. One of the best approach is to make use of the after trigger which clearly takes care of concurrency problems associated with mutating triggers .When after trigger is used only after the process of current updating is finished the next process gets processed.
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RE: What is mutating trigger? How do you resolve it?
if the trigger attempts to select or modify the table while the trigger has not completed (ie. table is in transition). then mutating trigger error occurs.
because the table is in middle of a transaction so it causes the trigger to mutate.
you can change the trigger to statement level and apply the logic there.
RE: What is mutating trigger? How do you resolve it?
Mutating trigger has similar concept to that of deadlock. When a table is in the half way of executing a transaction and is the owner of a trigger and if the same table is accessed by the trigger somewhere else in the same time then at that instance mutating trigger occurs.
RE: What is mutating trigger? How do you resolve it?
To avoid Mutating trigger there are many ways. One of the best approach is to make use of the after trigger which clearly takes care of concurrency problems associated with mutating triggers .When after trigger is used only after the process of current updating is finished the next process gets processed.
RE: What is mutating trigger? How do you resolve it?
If a trigger body is trying to update dependent tables the best approach in this case to avoid mutating trigger errors would be to make the transactions independent and not associated with triggers which is technically called as autonomous transactions.
RE: What is mutating trigger? How do you resolve it?If a trigger body is trying to update dependent tables, will it get a mutating error?
Mutating trigger is trigger that is currently being modified by DML opertion. For eg. You created a trigger trigger1 on table1 it should fire after update for each row. And you wrote some update statement on the same table (table1) inside the trigger . When you execute the individual update stmt on table1 the trigger get fires and the trigger also is currently being updated the same rows in table1 which is called mutating error and mutating trigger.
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