Prefetches and multiple-row fetches are different. Prefetches can be carried out without explicit instructions from the client application. Prefetching retrieves rows from the server into a buffer on the client side, but does not make those rows available to the client application until the application fetches the appropriate row.
By default, the SQL Anywhere client library prefetches multiple rows whenever an application fetches a single row. The SQL Anywhere client library stores the additional rows in a buffer.
Prefetching assists performance by cutting down on client/server round trips, and increases throughput by making many rows available without a separate request to the server for each row or block of rows.
For more information about controlling prefetches, see prefetch option.
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