Datatype conversion is handled differently for the transfer types. After converting the incoming source database datatypes, the access service does one of the following:
For bulk copy and express transfer processing, the source datatypes are converted into the actual datatypes of the target columns. If the source and target columns have incompatible datatypes, the transfer ends with an error.
For destination-template transfer processing, the datatype qualifiers specified are used, with the question marks in the template. When the question marks do not have qualifiers, the access service uses the datatypes of the source to determine the default qualifiers.
WARNING! DirectConnect cannot correctly transfer varchar values containing empty strings (zero length non-null strings), in the bulk copy and destination-template transfer process. Empty string varchar values are interpreted as NULL values. Express transfer processes this empty string correctly.
