Consider a case that we want to select rows containing name, designation, department from table name staff which are not present in table name Officers.
SELECT nameofStaff, designationofStaff, departmentofStaff FROM staff EXCEPT SELECT nameofOfficer, designationofOfficer, departmentofOfficer FROM Officers
Above script will provide us distinct records that are there in Staff table but are not present in Officers table. Number of columns should be same on both sides of EXCEPT. And data types of columns should also match.
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