20.Functions (Date)

SQL

Functions : Functions are pre-defined programs which returns always one value

Types of Functions: 1. Single Row Functions 2. Group Functions

Single Row Functions : The function which acts on each and every row.

Types of single row functions

  1. Characters / String Functions
  2. Numbers Functions
  3. Date functions
  4. Conversion Functions

Date Functions

Date Functions : Function which will return a value from the date

SQL> select sysdate from dual;

SYSDATE

24-APR-15

SQL> select next_day(sysdate,’monday’) from dual;

NEXT_DAY(

27-APR-15

SQL> select next_day(sysdate,’friday’) from dual;

NEXT_DAY(

01-MAY-15

sq> select months_between(’01-oct-2015′,’01-feb-2014′) from dual

MONTHS_BETWEEN(’01-OCT-2015′,’01-FEB-2014′)

                                     20

SQL> select greatest(’01-jan-2015′,’01-oct-2015′) from dual;

GREATEST(‘0

01-oct-2015

SQL> select months_between(sysdate,’01-feb-2014′) from dual;

MONTHS_BETWEEN(SYSDATE,’01-FEB-2014′)

                       14.7541767

SQL> select last_day(sysdate) from dual;

LAST_DAY(

30-APR-15

SQL> select last_day(’01-may-2015′)
2 from dual;

LAST_DAY(

31-MAY-15