In a MERGE statement, a variable cannot be set to a column and expression in the same assignment in the SET clause of an ...

In a MERGE statement, a variable cannot be set to a column and expression in the same assignment in the SET clause of an UPDATE action. Assignments of the form 'SET @variable = column = expression' are not valid in the SET clause of an UPDATE action in a MERGE statement. Modify the SET clause to only specify assignments of the form 'SET @variable = column' or 'SET @variable = expression'.