oracle tutorial

Oracle/PLSQL: COALESCE Function

This Oracle tutorial explains how to use the Oracle/PLSQL COALESCE function with syntax and examples.


The Oracle/PLSQL COALESCE function returns the first non-null expression in the list. If all expressions evaluate to null, then the COALESCE function will return null.


The syntax for the COALESCE function in Oracle/PLSQL is:

COALESCE( expr1, expr2, ... expr_n )

Parameters or Arguments

expr1, expr2, ... expr_n
The expressions to test for non-null values.

Applies To

The COALESCE function can be used in the following versions of Oracle/PLSQL:

  • Oracle 12c, Oracle 11g, Oracle 10g, Oracle 9i


The COALESCE function can be used in Oracle/PLSQL.

You could use the coalesce function in a SQL statement as follows:

SELECT COALESCE( address1, address2, address3 ) result
FROM suppliers;

The above COALESCE function is equivalent to the following IF-THEN-ELSE statement:

IF address1 is not null THEN
   result := address1;

ELSIF address2 is not null THEN
   result := address2;

ELSIF address3 is not null THEN
   result := address3;

   result := null;


The COALESCE function will compare each value, one by one.