PrefetchBuffer Connection Parameter [PBUF]

Sets the maximum amount of memory, in bytes, for buffering rows.

Usage

Anywhere

Values

Integer [ k | m }

Default

512 (KB)

Description

The PrefetchBuffer connection parameter controls the memory allocated on the client to store prefetched rows. The value is in bytes, but you can use k or m to specify units of kilobytes or megabytes. This connection parameter accepts values between 64KB and 8MB. In some circumstances, increasing the number of rows prefetched from the database server by the client can improve query performance. You can increase the number of rows prefetched using the PrefetchRows and PrefetchBuffer connection parameters.

Increasing the PrefetchBuffer (PBUF) connection parameter increases the amount of memory used to buffer GET DATA requests. This may improve performance for some applications that process many GET DATA (SQLGetData) requests.

Example

To determine if the PrefetchBuffer memory limit is reducing the number of prefetched rows, use this connection string fragment:

 ...prefetchrows=100;logfile=c:\ client.txt

To increase the memory limit to 256KB, use:

...prefetchrows=100;prefetchbuffer=256