set operators UNION,UNION ALL,INTERSECT,MINUS Privileges , Roles
SET OPERATORS · A set operator combines the result of two or more queries into one result. · Queries containing set operator are called compound queries. · No of columns and datatypes of the columns being selected must be same as all select statements used in the query and names of the columns need not be same. · Types of set operators 1. UNION 2. UNION ALL 3. INTERSECT 4. MINUS 1. UNION: - it will be written all rows from multiple queries by eliminating duplicate rows if any. Ø Select deptno, job from emp where deptno=10 UNION Select deptno, job from emp where deptno=20; 2. UNION ALL : - it will be written all rows from multiple queries by including duplicate ...