How to delete records from Child table and Parent table in a single query?
I have a master table and a details table. On delete cascade is not specified.
I want delete child开发者_JS百科 record as well as master record in a single query.
Suppose I want to delete EmployeeDetails and Employee record where EmpID=20 using a single query.
Is it possible?
Please help.
you cannot do it in a single query unless you have cascade delete
turned on or you have a trigger
on the PK table that will delete the FK table rows for that relationship
There is no construct in SQL that allows you to delete from two tables in a singe command. You can do that in a single "batch" or in a transaction (which will be preferable).
you could add a trigger on the child table to delete any other children and then the parent. This is not "technically" a single statement, but your application only needs to issue a single DELETE and it is all done for you.
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