DEFAULT_TABLE_UDF_ROW_COUNT Option

Enables you to override the default estimate of the number of rows to return from a table UDF (either a C, C++, or Java table UDF).

Allowed Values

0 to 4294967295

Default

200000

Scope

DBA permissions are required to set this option. Temporary only for the PUBLIC group.

Description

A table UDF can use the DEFAULT_TABLE_UDF_ROW_COUNT option to give the query processor an estimate for the number of rows that a table UDF will return. This is the only way a Java table UDF can convey this information. However, for a C or C++ table UDF, the UDF developer should consider publishing this information in the describe phase using the EXTFNAPIV4_DESCRIBE_PARM_TABLE_NUM_ROWS describe parameter to publish the number of rows it expects to return. The value of EXTFNAPIV4_DESCRIBE_PARM_TABLE_NUM_ROWS always overrides the value of the DEFAULT_PROXY_TABLE_UDF_ROW_COUNT option.