DB2 Version 9.7 for Linux, UNIX, and Windows

query_cost_estimate - Query cost estimate monitor element

Estimated cost for a query, as determined by the SQL compiler. This value is reported in timerons.

Table 1. Table Function Monitoring Information
Table Function	Monitor Element Collection Command and Level
MON_GET_ACTIVITY_DETAILS table function - Get complete activity details (reported in DETAILS XML document)	Always collected
MON_GET_PKG_CACHE_STMT table function - Get SQL statement activity metrics in the package cache	Always collected
MON_GET_PKG_CACHE_STMT_DETAILS table function - get detailed metrics for package cache entries	Always collected

Table 2. Snapshot Monitoring Information
Snapshot Level	Logical Data Grouping	Monitor Switch
Application	stmt	Statement
DCS Statement	dcs_stmt	Statement
Activities	event_activity	-
Package cache	-	COLLECT BASE DATA

Usage

This monitor element allows correlation of actual run-time with the compile-time estimates.

This element also returns information for the following SQL statements when you are monitoring DB2 Connect™.

PREPARE
Represents the relative cost of the prepared SQL statement.
FETCH
Contains the length of the row retrieved. Only collected if the DRDA® server is DB2® for OS/400®.

If information is not collected for a DRDA server, then the element is set to zero.

Note: If the DRDA server is DB2 for OS/390® and z/OS®, this estimate could be higher than 2**32 - 1 (the maximum integer number that can be expressed through an unsigned long variable). In that case, the value returned by the monitor for this element will be 2**32 - 1.