Bulk copy and express transfer initiate a direct transfer of data between two databases from the client application. You use a bulk copy or express transfer statement to copy large amounts of data between similar tables. The express transfer feature transfers data faster than bulk copy transfer, and because it uses the same syntax as the bulk copy transfer, you can use it without modifying your applications. For more information about express transfer, see “Express transfer”.
Table 9-1 describes the conditions that determine which type of transfer you select.
Use bulk copy transfer: |
Use express transfer: |
---|---|
When the source or destination database is ASE and does not use an ASE ODBC driver. |
When you use ODBC drivers for both the source and destination database. |
To exercise more control over transfer. |
To execute the transfer quickly. |
When you require diverse datatype conversions. |
When you do not require any datatype conversions. |
For bulk copy and express transfer, these limitations apply:
The transfer statement must be the only statement in a request.
The table (the target) into which you want to transfer data must already exist because the transfer statement does not create new tables.
The structure of the target table must match the structure of the source table.
For bulk copy and express transfer to work, the secondaryname to the secondary database must be recorded in these files:
For bulk copy transfer, the Windows sql.ini file or the UNIX interfaces file.
For express transfer, the secondaryname must match a data source name (DSN) in the odbc.ini file.
Unicode datatypes are not supported.
The first 32K of long character and long binary values are supported. Transfer processing truncates longer values without any warning.