Filemaker Pro 8.5 Educational Maintenance T3 TJ083LL/A User Manual

Chapter 8

  

|

  Logical functions     137

IsValid(field)

field - any 

number

Returns False (0) when:
•

A 

 contains an invalid value because of a data type mismatch (text in a date 

field, for example)

•

FileMaker Pro cannot locate (temporarily or permanently) the 

 in which 

the referenced field is defined

•

A field has been deleted from a related table, and therefore the references to that 
field in the parent table are invalid

Otherwise it returns 

 (the data is valid).

IsValid(Datefield) returns 

 if there is non-date data in Datefield, for example if text 

was 

IsValid(Amount) returns 

 if there is only text in the number field Amount.

IsValid(table::field) returns 

 if the related table was renamed and the 

relationship isn’t updated with the new filename.

IsValidExpression(expression)

expression - any calculation 

number