Use case when and grouping function together : CASE « Query Select « Oracle PL/SQL Tutorial






  1. Oracle PL/SQL Tutorial
  2. Query Select
  3. CASE
SQL>
SQL> create table emp
  2  ( empno      NUMBER(4)    constraint E_PK primary key
  3  , ename      VARCHAR2(8)
  4  , init       VARCHAR2(5)
  5  , job        VARCHAR2(8)
  6  , mgr        NUMBER(4)
  7  , bdate      DATE
  8  , sal       NUMBER(6,2)
  9  , comm       NUMBER(6,2)
 10  , deptno     NUMBER(2)    default 10
 11  ) ;

Table created.

SQL> insert into emp values(1,'Tom','N',   'TRAINER', 13,date '1965-12-17',  800 , NULL,  20);

1 row created.

SQL> insert into emp values(2,'Jack','JAM', 'Tester',6,date '1961-02-20',  1600, 300,   30);

1 row created.

SQL> insert into emp values(3,'Wil','TF' ,  'Tester',6,date '1962-02-22',  1250, 500,   30);

1 row created.

SQL> insert into emp values(4,'Jane','JM',  'Designer', 9,date '1967-04-02',  2975, NULL,  20);

1 row created.

SQL> insert into emp values(5,'Mary','P',  'Tester',6,date '1956-09-28',  1250, 1400,  30);

1 row created.

SQL> insert into emp values(6,'Black','R',   'Designer', 9,date '1963-11-01',  2850, NULL,  30);

1 row created.

SQL> insert into emp values(7,'Chris','AB',  'Designer', 9,date '1965-06-09',  2450, NULL,  10);

1 row created.

SQL> insert into emp values(8,'Smart','SCJ', 'TRAINER', 4,date '1959-11-26',  3000, NULL,  20);

1 row created.

SQL> insert into emp values(9,'Peter','CC',   'Designer',NULL,date '1952-11-17',  5000, NULL,  10);

1 row created.

SQL> insert into emp values(10,'Take','JJ', 'Tester',6,date '1968-09-28',  1500, 0,     30);

1 row created.

SQL> insert into emp values(11,'Ana','AA',  'TRAINER', 8,date '1966-12-30',  1100, NULL,  20);

1 row created.

SQL> insert into emp values(12,'Jane','R',   'Manager',   6,date '1969-12-03',  800 , NULL,  30);

1 row created.

SQL> insert into emp values(13,'Fake','MG',   'TRAINER', 4,date '1959-02-13',  3000, NULL,  20);

1 row created.

SQL> insert into emp values(14,'Mike','TJA','Manager',   7,date '1962-01-23',  1300, NULL,  10);

1 row created.

SQL>
SQL> select   deptno
  2  ,        case grouping(job)
  3                when 0 then job
  4                when 1 then 'total'
  5           end  job
  6  ,        count(empno) headcount
  7  from     emp
  8  group by ROLLUP(deptno, job);

    DEPTNO JOB       HEADCOUNT
---------- -------- ----------
        10 Manager           1
        10 Designer          2
        10 total             3
        20 TRAINER           4
        20 Designer          1
        20 total             5
        30 Tester            4
        30 Manager           1
        30 Designer          1
        30 total             6
           total            14

11 rows selected.

SQL>
SQL>
SQL> drop table emp;

Table dropped.

SQL>








2.15.CASE
2.15.1.Using the CASE Expression
2.15.2.The following example illustrates the use of a simple CASE expression:
2.15.3.Using Searched CASE Expressions
2.15.4.The following example illustrates the use of a searched CASE expression:
2.15.5.Use logical operators in a searched CASE expression
2.15.6.Use CASE statement to deal with NULL
2.15.7.Use case when and grouping function together
2.15.8.Use case when clause to decode value
2.15.9.Use case when statement with between ... and
2.15.10.Use case when statement with exists and subquery
2.15.11.Use case when statement with in()
2.15.12.Use case when statement with to_char() like
2.15.13.Use case when with comparasion operator
2.15.14.Use Case to output null value
2.15.15.Wrap case when into sum() function