一个Shell小脚本精准统计Mysql每张表的行数实现

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 database
information_schema
mysql
performance_schema
shijiange
test
wordpress

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
> done
information_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
> done
information_schema.character_sets  40
information_schema.collations  219
information_schema.collation_character_set_applicability  219
information_schema.columns 1789
information_schema.column_privileges  0
shijiange.logincount  4
shijiange.member  0
shijiange.user 2097153
test.detect_servers 0
wordpress.wp_commentmeta  0
wordpress.wp_comments  0
wordpress.wp_links 0
wordpress.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=127.0.0.1
mysqluser=xxx
mysqlpassword=xxx

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

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 2
shijiange.user 2097153
information_schema.innodb_buffer_page  8191
performance_schema.events_waits_summary_by_thread_by_event_name 5320
information_schema.innodb_buffer_page_lru  3453

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。