Difference between revisions of "NVL()"

From Recital Documentation Wiki
Jump to: navigation, search
 
Line 12: Line 12:
  
 
==See Also==
 
==See Also==
[[ETOS()]], [[ISNULL()]], [[SET NULL]]
+
[[ETOS()]], [[ISNULL()]], [[SET NULL]], [[SET NULLDISPLAY]]
  
  
Line 33: Line 33:
 
[[Category:Documentation]]
 
[[Category:Documentation]]
 
[[Category:Functions]]
 
[[Category:Functions]]
 +
[[Category:Expressions and Type Conversion]]
 +
[[Category:Expressions and Type Conversion Functions]]

Revision as of 11:46, 9 June 2009

Class

Expressions and Type Conversion


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