NPGTHRSH in macro DSN6SPRM
Specifies that Db2 favors matching index access, through the index with the most matching columns, for tables or partitions that have fewer data pages than the specified value.
Db2 compares the NPGTHRSH value to the NPAGESF
column in the SYSIBM.SYSTABLES catalog table for table-level comparisons and the NPAGES column of
the SYSIBM.SYSTABSTATS table for partition-level comparisons. 
Tip: For best results, set NPGTHRSH
to a non-zero value so that Db2 uses
matching index access for tables with default statistics. For more information, see Favoring index access.
For best results, set NPGTHRSH
to a non-zero value so that Db2 uses
matching index access for tables with default statistics. For more information, see Favoring index access.| Acceptable values: | 0, 1–2147483647 |
|---|---|
| Default: | 1 1 |
| DSNZPxxx: | DSN6SPRM NPGTHRSH |
| Security parameter: | No |
Note:
- For SAP installations, the default value is 10.
- 1–2147483647
- Db2 uses matching index access for queries that access a table or partition that contains fewer data pages than the specified NPGTHRSH value. Db2 uses the index with the most matching columns.For default statistics (-1), Db2 12 uses the -1 values for the comparison.
- 0
- Db2 always chooses the access path based on cost estimates, regardless of the number of data pages that statistics indicate for the table or partition.