NVL2
Syntax
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 data type. The arguments expr2 and expr3 can have any data types except LONG.
If the data types of expr2 and expr3 are different, then Oracle Database implicitly converts one to the other. If they cannot be converted implicitly, then the database returns an error. If expr2 is character or numeric data, then the implicit conversion is implemented as follows:
-
If
expr2is character data, then Oracle Database convertsexpr3to the data type ofexpr2before returning a value unlessexpr3is a null constant. In that case, a data type conversion is not necessary, and the database returnsVARCHAR2in the character set ofexpr2. -
If
expr2is numeric data, then Oracle Database determines which argument has the highest numeric precedence, implicitly converts the other argument to that data type, and returns that data type.
See Also:
-
Table 2-8 for more information on implicit conversion and "Numeric Precedence" for information on numeric precedence
-
Appendix C in Oracle Database Globalization Support Guide for the collation derivation rules, which define the collation assigned to the return value of
NVL2when it is a character value
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 6820
Bates 7300 8395
Bell 4000 4000
Bernstein 9500 11875
Bissot 3300 3300
Bloom 10000 12000
Bull 4100 4100