4D v16.3

Is field value Null

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4D v16.3
SQL
Is field value Null

Is field value Null 


 

Is field value Null ( aField ) -> Function result 
Parameter Type   Description
aField  Field in Field to be evaluated
Function result  Boolean in True = field is NULL, False = field is not NULL

The Is field value Null command returns True if the field designated by the aField parameter contains the NULL value, and False otherwise.

The NULL value is used by the SQL kernel of 4D. For more information, refer to the 4D SQL Reference manual.

The value returned by this command is only meaningful if the "Map NULL values to blank values" option is not checked in the field definition of the Structure editor. Otherwise, it always returns False.



See also 

SET FIELD VALUE NULL

 
PROPERTIES 

Product: 4D
Theme: SQL
Number: 964

This command can be run in preemptive processes

 
HISTORY 

Created: 4D v11 SQL

 
ARTICLE USAGE

4D Language Reference ( 4D v16)
4D Language Reference ( 4D v16.1)
4D Language Reference ( 4D v16.2)
4D Language Reference ( 4D v16.3)