Selecting the Conversion Function
For a value returned from a database operation, use Database Variant to Data rather than the generic Variant to Data function. A Boolean constant can define the requested output type, but successful conversion alone does not prove that the selected function or type is appropriate.
Wiring the Boolean Output Type
Wire the database-returned variant to the conversion function and provide a Boolean constant or control as the type specifier. The resulting output should then be treated as a Boolean database value and connected only to logic that expects that representation.
Verification Procedure
- Read one database field whose expected value is Boolean.
- Wire that value to Database Variant to Data.
- Wire a Boolean constant or control as the requested data type.
- Compare the converted output with the value stored in the database before using it in application logic.
FAQ
Should I use Variant to Data or Database Variant to Data in LabVIEW?
Use Database Variant to Data when the input variant is returned by a database operation. Reserve the wiring described here for a Boolean destination type.
What does the Boolean constant do on the conversion function?
The Boolean constant specifies Boolean as the requested output representation for the converted database value.
How do I verify a LabVIEW database Boolean conversion?
Convert one known database value with Database Variant to Data, specify Boolean output, and compare the result with the value stored in the database.
