NVL2

Syntax

Description of the illustration nvl2.gif

Purpose

NVL2 lets you determine the value returned by a query based on whether a specified expression is null or not null. If expr1 is not null, then NVL2 returns expr2. If expr1 is null, then NVL2 returns expr3.

The argument expr1 can have any datatype. The arguments expr2 and expr3 can have any datatypes except LONG.

If the datatypes of expr2 and expr3 are different:

• If expr2 is character data, then Oracle Database converts expr3 to the datatype of expr2 before comparing them unless expr3 is a null constant. In that case, a datatype conversion is not necessary. Oracle returns VARCHAR2 in the character set of expr2.

• If expr2 is numeric, then Oracle determines which argument has the highest numeric precedence, implicitly converts the other argument to that datatype, and returns that datatype.

  
  

  See Also: Table 2-10, "Implicit Type Conversion Matrix" for more information on implicit conversion and "Numeric Precedence" for information on numeric precedence

  
  

Examples

The following example shows whether the income of some employees is made up of salary plus commission, or just salary, depending on whether the commission_pct column of employees is null or not.

SELECT last_name, salary, NVL2(commission_pct, 
   salary + (salary * commission_pct), salary) income
   FROM employees WHERE last_name like 'B%'
   ORDER BY last_name;

LAST_NAME                     SALARY     INCOME
------------------------- ---------- ----------
Baer                           10000      10000
Baida                           2900       2900
Banda                           6200       6882
Bates                           7300       8468
Bell                            4000       4000
Bernstein                       9500      11970
Bissot                          3300       3300
Bloom                          10000      12100
Bull                            4100       4100