Difference between revisions of "NVL()"
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==See Also== | ==See Also== | ||
| − | [[ | + | [[COALESCE()]], [[EMPTY()]], [[ETOS()]], [[EVL()]], [[IFNULL()]], [[ISNULL()]], [[SET NULL]], [[SET NULLDISPLAY]] |
==Description== | ==Description== | ||
Latest revision as of 05:35, 15 April 2013
Contents
Purpose
Function to specify an alternative value for a null expression
Syntax
NVL(<expr1>,<expr2>)
See Also
COALESCE(), EMPTY(), ETOS(), EVL(), IFNULL(), ISNULL(), SET NULL, SET NULLDISPLAY
Description
The NVL() function evaluates the expression in <expr1>, and if the expression does not evaluate to NULL, the evaluated result is returned. If the expression in <expr1> does evaluate to NULL, the expression in <expr2> is evaluated. If <expr2> does not evaluate to NULL, the evaluated result is returned. If both <expr1> and <expr2> evaluate to NULL, the NVL() function returns NULL.
Example
set null on CREATE TABLE nullon (firstname c(20), lastname c(20)) INSERT INTO nullon (lastname) VALUES ("Smith") SELECT lastname, nvl(firstname,"Unknown") from nullon
