Performance aspects of bulk operations

The performance of bulk operations depends on several factors, including whether the operation is internal or external to the database server.

Internal bulk operations

Internal bulk operations, also referred to as server-side bulk operations, are import and export operations performed by the database server using the LOAD TABLE, and UNLOAD statements.

When performing internal bulk operations, you can load from, and unload to, ASCII text files, or Adaptive Server Enterprise BCP files. These files can exist on the same computer as the database server, or on a client computer. The specified path to the file being written or read is relative to the database server. Internal bulk operations are the fastest method of importing and exporting data into the database.

External bulk operations

External bulk operations, also referred to as client-side bulk operations, are import and export operations performed by a client such as Interactive SQL, using INPUT and OUTPUT statements. When the client issues an INPUT statement, an INSERT statement is recorded in the transaction log for each row that is read when processing the file specified in the INPUT statement. As a result, client-side loading is considerably slower than server-side loading. As well, INSERT triggers fire during an INPUT.

The OUTPUT statement allows you to write the result set of a SELECT statement to many different file formats.

For external bulk operations, the specified path to the file being read or written is relative to the computer on which the client application is running.