Good Morning friends today we will discuss about the concept of COALESCE in ORACLE..

COALESCE returns the first non-null expr in the expression list. You must specify at least two expressions. If all occurrences of expr evaluate to null, then the function returns null.

Syntax: COALESCE (expr1, expr2);

This is equivalent to

CASE WHEN expr1 IS NOT NULL THEN expr1 ELSE expr2 END;

Example 1:

Select  COALESCE (1*2,3+4) FROM DUAL;

Output  1 :

2

Example 2:

Select  COALESCE (NULL,3+4) FROM DUAL;

Output 2:

7

Thankyou...!!!!