mysql基本命令

1.explain

explain是mysql的查詢分析計劃

explain select * from user \G;

explain的partitions操做

explain partitions select * from user

explain的extended操做提供explain額外的filtered列

explain extended select * from test1 t1 inner join test2 t2 using(uid)

2.show warnings

關於show可參考mysql文檔http://dev.mysql.com/doc/refman/5.7/en/show.html

show warnings用於查看生成的 警告

show warnings \G;

3.show create table

show create table用於呈現表的基本信息

show create table user \G;

4.show indexes

show indexes查看索引信息

show indexes from user \G;

5.show table status

show table status用於查看數據表的大小、結構信息

show table status like 'user' \G;

6.show status

show global status

show session status like 'kk';

7.show engine status命令

show engine status命令用查看mysql使用引擎的狀態,爲了方便重定向輸出的文本文件，並\G格式化

mysql -e "show engine innodb status\G" -u[name] -p[password] [database] > /usr/local/status.txt

8.show procedure status查看存儲過程狀態

8.1查看數據庫全部存儲過程狀態

mysql> SHOW PROCEDURE STATUS\G
*************************** 1. row ***************************
                  Db: test
                Name: sp1
                Type: PROCEDURE
             Definer: testuser@localhost
            Modified: 2004-08-03 15:29:37
             Created: 2004-08-03 15:29:37
       Security_type: DEFINER
             Comment:
character_set_client: latin1
collation_connection: latin1_swedish_ci
  Database Collation: latin1_swedish_ci

8.2查看指定存儲過程的狀態

mysql> SHOW PROCEDURE STATUS LIKE 'sp1'\G
*************************** 1. row ***************************
                  Db: test
                Name: sp1
                Type: PROCEDURE
             Definer: testuser@localhost
            Modified: 2004-08-03 15:29:37
             Created: 2004-08-03 15:29:37
       Security_type: DEFINER
             Comment:
character_set_client: latin1
collation_connection: latin1_swedish_ci
  Database Collation: latin1_swedish_ci

 

9.設置數據字符編碼集

在使用數據庫時有時可能須要改變數據的字符編碼

9.1查看當前數據的編碼

//toggle
mysql> use xxx;
//查看數據庫編碼
mysql>show variables like 'character_set_database';
//update CHARACTER
mysql>alter database xxx CHARACTER SET utf-8;

10.獲取數據庫表的schema

SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'edu' AND TABLE_NAME = 't_boss';

11.獲取數據表每一列的schema

show columns from pma_designer_coords;