DB2对于SQL执行计划的explain表,默认都是不存在的,所以需要在使用过程中根据需要创建,那么如何创建呢?其实DB2还是提供了多种
DB2对于SQL执行计划的explain表,默认都是不存在的,所以需要在使用过程中根据需要创建,,那么如何创建呢?其实DB2还是提供了多种方法供大家使用,第一种就是默认使用脚本EXPLAIN.DDL,该脚本默认创在数据库的如下路径中:
C:\Program Files (x86)\IBM\SQLLIB\MISC>ls
DB2AutoBackupPolicy.xsd DB2EvmonPkgCache.xsd DB2MonRoutines.xsd DB2SchemaAnnotation.xsl db2adminV8.exe db2uext2.v2
DB2AutoReorgPolicy.xsd DB2EvmonUOW.xsd DB2OptProfile.xsd EXPLAIN.DDL db2audit.ddl wlmevmon.ddl
DB2AutoRunstatsPolicy.xsd DB2MaintenanceWindowPolicy.xsd DB2PolicyLang.xsd db2InstallReg.exe db2ckupgrade.exe
DB2EvmonLocking.xsd DB2MonCommon.xsd DB2RecommendationSchema.xsd db2InstallReg.txt db2hdr.exe
所以只需要在连接到指定库,执行该文件即可创建explain表,
db2 connect to sample
db2 -tvf EXPLAIN.DDL
即可成功创建,默认的表的schema就是当前的用户schema。
但是这个需要有相关文件才可,也可以通过如下SP直接创建:
db2 connect to sample
db2 "CALL SYSPROC.SYSINSTALLOBJECTS('EXPLAIN','C',NULL,'DB2INST1')"
这样指定Schmma创建explain表,成功后就可以进行SQL执行计划分析了。
DB2数据库性能调整和优化(第1、2版) PDF
DB2数据库性能优化介绍
DB2 9.7 for Linux 5.4安装详细步骤
本文永久更新链接地址:

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