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1、MySQL性能跟踪语句教程PHP程序开发快，运行快，技术本身学习快。嵌入于HTML：因为 PHP可以被嵌入于 HTML语言，它相对于其他语言。简单，实用性强，更适合初学者。以下是为大家搜索 MySQL性能跟踪语句教程，希望能给大家带来帮助 ! 更多精彩内容请及时关注我们 !1 、不过版本要在之后手册上介绍：ImportantPleasenotethattheSHOWPROFILEandSHOWPROFILESfunctionalityisp artoftheMySQL5.0CommunityServeronly.2、变量 profiling是用户变量，每次都得重新启用。以下是我做的一些实验。数
2、据很明显，就不多解释了。mysqlusetestDatabasechangedmysqlsetprofiling=1;QueryOK,0rowsaffected(0.00sec)mysqlshowtables;+-+|Tables_in_test|+-+|bag_item|bag_user|score|t|+-+4rowsinset(0.03sec)mysqlselectcount(*)fromt;+-+|count(*)|+-+|2097152|+-+1rowinset(0.74sec)mysqlshowprofiles;+-+-+-+|Query_ID|Duration|Query|+-+
3、-+-+|1|0.02717000|showtables|2|0.74770100|selectcount(*)fromt|+-+-+-+2rowsinset(0.00sec)mysqlshowprofileforquery2;+-+-+|Status|Duration|+-+-+|(initialization)|0.000004|checkingquerycacheforquery|0.000044|Openingtables|0.000012|Systemlock|0.000017|Tablelock|0.00003|init|0.000013|optimizing|0.000008|s
4、tatistics|0.000013|preparing|0.000011|executing|0.000006|Sendingdata|0.747313|end|0.000014|queryend|0.000006|storingresultinquerycache|0.000006|freeingitems|0.000012|closingtables|0.000009|loggingslowquery|0.000183|+-+-+17rowsinset(0.00sec)mysqlshowprofileblockio,cpuforquery2;+-+-+-+- -+-+-+|Status|
5、Duration|CPU_user|CPU_system|Block_ops_in|Block_ops _out|+-+-+-+- -+-+-+|(initialization)|0.000004|0|0|0|0|checkingquerycacheforquery|0.000044|0|0|0|0|Openingtables|0.000012|0|0|0|0|Systemlock|0.000017|0|0|0|0|Tablelock|0.00003|0|0|0|0|init|0.000013|0|0|0|0|optimizing|0.000008|0|0|0|0|statistics|0.0
6、00013|0|0|0|0|preparing|0.000011|0|0|0|0|executing|0.000006|0|0|0|0|Sendingdata|0.747313|0.746887|0|0|0|end|0.000014|0|0|0|0|queryend|0.000006|0|0|0|0|storingresultinquerycache|0.000006|0|0|0|0|freeingitems|0.000012|0|0|0|0|closingtables|0.000009|0|0|0|0|loggingslowquery|0.000183|0|0|0|0|+-+-+-+- -+
7、-+-+17rowsinset(0.00sec)mysqlinsertintot(username)selectusernamefromt;QueryOK,2097152rowsaffected(34.17sec)Records:2097152Duplicates:0Warnings:0mysqlshowprofiles;+-+-+-+|Query_ID|Duration|Query|+-+-+- -+|1|0.02717000|showtables|2|0.74770100|selectcount(*)fromt|3|0.00004200|showprifileforquery2|4|34.
8、30410100|insertintot(username)selectusernamefromt|+-+-+-+4rowsinset(0.00sec)mysqlshowprofilecpu,blockio,memory,swapsforquery4;+-+-+-+- -+-+-+-+|Status|Duration|CPU_user|CPU_system|Block_ops_in|Block_ops _out|Swaps|+-+-+-+-+-+-+-+|(initialization)|0.000038|0|0|0|0|0|checkingpermissions|0.000016|0|0|0
9、|0|0|Openingtables|0.000014|0|0|0|0|0|Systemlock|0.000007|0|0|0|0|0|Tablelock|0.000013|0|0|0|0|0|init|0.000015|0|0|0|0|0|optimizing|0.000006|0|0|0|0|0|statistics|0.000012|0|0|0|0|0|preparing|0.000011|0|0|0|0|0|Creatingtmptable|0.000029|0|0|0|0|0|executing|0.000005|0|0|0|0|0|Copyingtotmptable|1.26287
10、7|1.24981|0.012998|0|0|0|convertingHEAPtoMyISAM|0.384814|0.187971|0.19797|0|0|0|Copyingtotmptableondisk|1.417069|1.203817|0.191971|0|0|0|Sendingdata|31.104185|13.965877|0.843872|0|0|0|end|0.000017|0|0|0|0|0|removingtmptable|0.134872|0|0.029995|0|0|0|end|0.000026|0|0|0|0|0|queryend|0.000006|0|0|0|0|0|freeingitems|0.000011|0|0|0|0|0|clo
