Difference between revisions of "NVL()"

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(Class)
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==Class==
 
Expressions and Type Conversion
 
  
  

Revision as of 15:26, 28 October 2009


Purpose

Function to specify an alternative value for a null expression


Syntax

NVL(<expr1>,<expr2>)


See Also

ETOS(), 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 sql to vfp
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


Products

Recital Database Server, Recital Mirage Server, Recital Terminal Developer