Use if logic in Oracle SQL statements

L Use If-then-else logic in SQL statements LL uses two methods: CASE expression: SQL99 syntax, similar to basic, cumbersome decode functions: Oracle's own syntax, Java-like, comparative introduction

1Sql> SelectEname,job, Sal, CaseJob when 'President'  Then 1.1*Sal2   2                                when 'MANAGER'  Then 1.2*Sal3   3                                 when 'Clerk'  Then 1.3*Sal4   4                                 Else 1.4*Sal5   5                                Endsalary after rise6   6   fromEMP7   7  ;8  9 ename JOB SAL salary after riseTen ---------- --------- --------- ---------- OneSMITH Clerk800.00       1040 AALLEN salesman1600.00       2240 -WARD salesman1250.00       1750 -JONES MANAGER2975.00       3570 theMARTIN salesman1250.00       1750 -BLAKE MANAGER2850.00       3420 -CLARK MANAGER2450.00       2940 -KING President5000.00       5500 +TURNER salesman1500.00       2100 -JAMES Clerk950.00       1235 +FORD ANALYST3000.00       4200 AMILLER Clerk1400.00       1820 atjack_12342000.00       2800 -   -  -rows Selected -  -Sql> SelectEname,job, Sal,decode (Job,'President',1.1*Sal, -   2                                   'MANAGER',1.2*Sal, in   3                                   'Clerk',1.3*Sal, -   4                                           1.4*Sal) pay rise after to   5   fromEMP; +   - ename JOB SAL salary after rise the ---------- --------- --------- ---------- *SMITH Clerk800.00       1040 $ALLEN salesman1600.00       2240Panax NotoginsengWARD salesman1250.00       1750 -JONES MANAGER2975.00       3570 theMARTIN salesman1250.00       1750 +BLAKE MANAGER2850.00       3420 ACLARK MANAGER2450.00       2940 theKING President5000.00       5500 +TURNER salesman1500.00       2100 -JAMES Clerk950.00       1235 $FORD ANALYST3000.00       4200 $MILLER Clerk1400.00       1820 -jack_12342000.00       2800 -   the  -Rows selected

Use if logic in Oracle SQL statements