db2 access plan

db2 connect to EFEDDB2T

db2 -tvf E:\diskd\IBM\SQLLIB\MISC\EXPLAIN.DDL

db2 set current explain mode explain

C:\Users\Administrator>db2 set current schema DBEFMSVR
DB20000I  SQL 命令成功完成。

C:\Users\Administrator>db2 -tvf C:\Users\Administrator\Desktop\test.txt

DB21007E  读该命令时已达到文件末尾。

C:\Users\Administrator>db2 -td$ -f C:\Users\Administrator\Desktop\test.txt
SQL0217W  当仅在处理 Explain 信息请求时不执行语句。  SQLSTATE=01604

C:\Users\Administrator>db2exfmt -d EFEDDB2T -g TIC -w -l -n % -s % -# 0 -o explain_plan.txt
DB2 Universal Database Version 10.1, 5622-044 (c) Copyright IBM Corp. 1991, 2011

Licensed Material - Program Property of IBM
IBM DATABASE 2 Explain Table Format Tool

Connecting to the Database.
Connect to Database Successful.
Binding package - Bind was Successful
Enter up to 26 character Explain timestamp (Default -1) ==>
Output is in explain_plan.txt.
Executing Connect Reset -- Connect Reset was Successful.

C:\Users\Administrator>

会生成大量的explain信息，类似于：

Access Plan:
-----------
 Total Cost:   42.6955
 Query Degree:  1

              Rows
             RETURN
             (   1)
              Cost
               I/O
               |
             1.73692
             ^NLJOIN
             (   2)
             42.6955
               42
         /-----+------\
     1.73692             1
     TBSCAN           IXSCAN
     (   3)           (   4)
     42.6839         0.0092883
       42                0
       |                |
       707              67
 TABLE: DBEFMSVR  INDEX: DBEFMSVR
 FMST_O_POOL_EE   CC1353485185765
       Q1               Q2