一个Shell小脚本精准统计Mysql每张表的行数

前言

对于开发或者运维人员来说，Mysql数据库每张表的数量肯定是要了解下，有助于我们清理无用数据或者了解哪张表比较占用空间。
另外多次统计表的行数，还能发现Mysql表的增量情况，能够预测表未来会有多大的量。
废话不多说，直接带大家写一个简单的Shell小脚本

循环获取数据库名

直接上Shell代码，show databases获取所有的库名。结果有一个我们不想要的，就是Database，这个grep -v掉，轻松获取所有数据库

[root@shijiangeit ~]# mysql -h 127.0.0.1 -uxxx -pxxx -e "show databases;" 2>/dev/null+--------------------+| Database           |+--------------------+| information_schema || mysql              || performance_schema || shijiange          || test               || wordpress          |+--------------------+

[root@shijiangeit ~]# mysql -h 127.0.0.1 -uxxx -pxxx -e "show databases;" 2>/dev/null |grep -v Databaseinformation_schemamysqlperformance_schemashijiangetestwordpress

循环获取所有表

有了库信息，获取所有表就简单了，直接上Shell代码。show tables获取所有表名，其中Tables_in不需要，grep -v掉。

[root@shijiangeit ~]# for onedb in $(mysql -h 127.0.0.1 -uxxx -pxxx -e "show databases;" 2>/dev/null |grep -v Database);do>   echo $onedb>   mysql -h 127.0.0.1 -uxxx -pxxx $onedb -e "show tables" 2>/dev/null> doneinformation_schema+---------------------------------------+| Tables_in_information_schema          |+---------------------------------------+| CHARACTER_SETS                        || COLLATIONS                            || COLLATION_CHARACTER_SET_APPLICABILITY || COLUMNS                               || COLUMN_PRIVILEGES                     || ENGINES                               || EVENTS                                || FILES                                 || GLOBAL_STATUS                         || GLOBAL_VARIABLES                      || KEY_COLUMN_USAGE                      |

循环统计每张表的行数

取出库名加表名，一个select count(1)统计表的行数，循环统计，直接上Shell代码。

[root@shijiangeit ~]# for onedb in $(mysql -h 127.0.0.1 -uxxx -pxxx -e "show databases;" 2>/dev/null |grep -v Database);do>   for onetab in $(mysql -h 127.0.0.1 -uxxx -pxxx $onedb -e "show tables" 2>/dev/null |grep -v 'Tables_in_');do>     onetablength=$(mysql -h 127.0.0.1 -uxxx -pxxx $onedb -e "select count(1) from $onetab" 2>/dev/null |grep -v 'count')>     echo -e "$onedb.$onetab\t$onetablength">   done> doneinformation_schema.CHARACTER_SETS   40information_schema.COLLATIONS   219information_schema.COLLATION_CHARACTER_SET_APPLICABILITY    219information_schema.COLUMNS  1789information_schema.COLUMN_PRIVILEGES    0shijiange.logincount    4shijiange.member    0shijiange.user  2097153test.detect_servers 0wordpress.wp_commentmeta    0wordpress.wp_comments   0wordpress.wp_links  0wordpress.wp_options    156

变量化，脚本直接用

需要统计哪个Mysql，前面三个变量一改，立马就能统计所有表的大小了。

mysqlhost=127.0.0.1mysqluser=xxxmysqlpassword=xxxfor onedb in $(mysql -h $mysqlhost -u$mysqluser -p$mysqlpassword -e "show databases;" 2>/dev/null |grep -v Database);do  for onetab in $(mysql -h $mysqlhost -u$mysqluser -p$mysqlpassword $onedb -e "show tables" 2>/dev/null |grep -v 'Tables_in_');do    onetablength=$(mysql -h $mysqlhost -u$mysqluser -p$mysqlpassword $onedb -e "select count(1) from $onetab" 2>/dev/null |grep -v 'count')    echo -e "$onedb.$onetab\t$onetablength"  donedone

想看哪张表的行数最多？

之前的脚本加个 |sort -nrk 2|less 搞定，超实用的小脚本就这样完成了

[root@shijiangeit ~]# for onedb in $(mysql -h $mysqlhost -u$mysqluser -p$mysqlpassword -e "show databases;" 2>/dev/null |grep -v Database);do>   for onetab in $(mysql -h $mysqlhost -u$mysqluser -p$mysqlpassword $onedb -e "show tables" 2>/dev/null |grep -v 'Tables_in_');do>     onetablength=$(mysql -h $mysqlhost -u$mysqluser -p$mysqlpassword $onedb -e "select count(1) from $onetab" 2>/dev/null |grep -v 'count')>     echo -e "$onedb.$onetab\t$onetablength">   done> done | sort -nrk 2shijiange.user  2097153information_schema.INNODB_BUFFER_PAGE   8191performance_schema.events_waits_summary_by_thread_by_event_name 5320information_schema.INNODB_BUFFER_PAGE_LRU   3453