SQL Rollup Grouping Cube

These are the enhancements to the group by feature.

USING ROLLUP

This will give the salaries in each department in each job category along with the total salary for individual departments and the total salary of all the departments.

SQL> Select deptno,job,sum(sal) from emp group by rollup(deptno,job);

                        DEPTNO   JOB         SUM(SAL)

                        ----------  ---------   ----------

        10    CLERK           1300

        10    MANAGER     2450

        10    PRESIDENT   5000

        10                              8750

        20    ANALYST       6000

        20    CLERK           1900

        20    MANAGER     2975

        20                             10875

        30    CLERK             950

        30    MANAGER      2850

        30    SALESMAN     5600

        30                              9400

                                          29025

USING GROUPING

 In the above query it will give the total salary of the individual departments but with a blank in the job column and gives the total salary of all the departments with blanks in deptno and job columns.

 To replace these blanks with your desired string grouping will be used

 SQL> select decode(grouping(deptno),1,'AllDepts',deptno),decode(grouping(job),1,'All  jobs',job),sum(sal) from emp group by rollup(deptno,job);

DECODE(GROUPING(DEPTNO),1,'ALLDEPTS',DEP DECODE(GR   SUM(SAL)

-----------------------------------  ----------------------------------    --------------

10                                                        CLERK             1300

10                                                         MANAGER                 2450

10                                                        PRESIDENT               5000

10                                                        All jobs                       8750

20                                                        ANALYST                   6000

20                                                        CLERK                        1900

20                                                        MANAGER                  2975

20                                                        All jobs                         10875

30                                                        CLERK                          950

30                                                        MANAGER                  2850

30                                                        SALESMAN                 5600

30                                                        All jobs                          9400

All Depts                                             All jobs                        29025

   Grouping will return 1 if the column which is specified in the grouping function has been used in rollup.

Grouping will be used in association with decode.

USING CUBE

This will give the salaries in each department in each job category, the total salary for individual departments, the total salary of all the departments and the salaries in each job category.

SQL> select decode(grouping(deptno),1,’All pts’,deptno),decode(grouping(job),1,’All

        Jobs’,job),sum(sal) from emp group by cube(deptno,job);

DECODE(GROUPING(DEPTNO),1,'ALLDEPTS',DEP DECODE(GR   SUM(SAL)

-----------------------------------  ------------------------------------  ------------

10                                            CLERK                         1300

10                                            MANAGER                              2450

10                                            PRESIDENT                           5000

10                                            All Jobs                                  8750

20                                            ANALYST                               6000

20                                            CLERK                         1900

20                                            MANAGER                              2975

20                                            All Jobs                               10875

30                                            CLERK                            950

30                                            MANAGER                               2850

30                                            SALESMAN                             5600

30                                            All Jobs                                  9400

All Depts                                            ANALYST                               6000

All Depts                                            CLERK                         4150

All Depts                                            MANAGER                              8275

All Depts                                            PRESIDENT                           5000

All Depts                                            SALESMAN                             5600

All Depts                                            All Jobs                               29025