For the buffer object handle, the AVAILABLE attribute corresponds to the AVAILABLE function. If the buffer contains a record, AVAILABLE is TRUE. Otherwise, AVAILABLE is FALSE.
Generally, a buffer-field object handle corresponds to a field returned in a query buffer. However, this field can be excluded from the query using a field list. In this case, if you try to read the BUFFER-VALUE attribute on the associated buffer-field object handle, the AVM returns an error indicating that the corresponding field is missing from the query buffer. You can use the AVAILABLE attribute to test whether the corresponding field was included or excluded from the query.
Depending on its return value, the AVAILABLE attribute indicates one of the following conditions when applied to the buffer-field object:
TRUE — The query buffer has a record with a field available that corresponds to this buffer-field object handle.
FALSE — The query buffer has a record with the field missing that corresponds to this buffer-field object handle.
Unknown value (?) — The query buffer associated with this buffer-field object handle has no record.
TRUE — The query buffer has a record with a field available that corresponds to this buffer-field object handle.