DB2 SQL文執行計劃監控簡介
DB2 SQL文執行計劃監控是DB2數據庫監控的重要組成部分，下面就讓我們來了解一下什么是DB2 SQL文執行計劃監控。
靜態的sql文執行計劃存放在系統的catalog表中，動態sql文的執行計劃存放在global package cache。
如果要使用explain工具，首先要創建相關的表，建表腳本在/misc/EXPLAIN.DDL，只要運行過一次explain GUI工具，將自動創建這些表。
explain特定注冊器類型：
CURRENT EXPLAIN MODE - Used to populate only the explain data. No snapshot will be taken.
CURRENT EXPLAIN SNAPSHOT - Used to capture only the explain snapshot data.
設置explain特定注冊器類型：
SET CURRENT EXPLAIN MODE option
SET CURRENT EXPLAIN SNAPSHOT option
The explain registers options are:
NO - No explain information is captured for dynamic SQL statements.
YES - Explain tables or snapshot information will be populated for dynamic SQL statements while executing the SQL statement, and the result is returned.
EXPLAIN - Explain tables or snapshot information will be populated for dynamic SQL statements without executing the SQL statement. Use this state to obtain explain information without executing the SQL statement.
【編輯推薦】
