Purpose
This control enables users to specify the maximum number of import data file records that can be sent within an SQL request's USING data buffer.
Syntax
where the following is true:
- n
- Integer in the range of 0 to 999900.
0 is the default value. Zero means that use of a PACK factor has not been specified, and PACK statistics are not generated for the import.
Entering an invalid n value prompts the following error message:*** Error: Pack factor value must be in the 0..999900 range.
- REQBUFLEN
- Defines the maximum request buffer size (in bytes) that can be used for an import. The request buffer stores the SQL statement, plus packed records (USING data), plus metadata. The larger the value, the more records can be packed. However, a larger request buffer could affect performance. Thorough testing should be performed before using this option in a production environment.
Usage Notes
The pack factor is reducible to prevent a USING data buffer overflow. BTEQ packs as many records into the request buffers as will fit. To prevent CLI buffer overflow errors, BTEQ considers both the upper limit, indicated by the pack factor, and CLI's maximum message size.
BTEQ enforces the database's limit for maximum packed records allowed in a iterated request. If the supplied pack factor exceeds the database maximum, BTEQ will display a warning message and will reset the pack factor to the allowed limit.
When a pack factor is used, statistics are created for the average and largest factor used as part of the summary messages for the request's result. If the REQBUFLEN option is defined, an extra statistical line will be added for the requested value and the actual bytes allocated for the request buffer.
A pack factor is established by using the PACK command or by using a PACK clause for the REPEAT command. See REPEAT.