mysql 常用语句(持续更新)
1 登录mysql
[[email protected] ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor.
2 显示mysql中有哪些数据库
mysql> show databases;
3 创建数据库
mysql> create database trace;
Query OK, 1 row affected (0.00 sec)
4 使用数据库trace
mysql> use trace;
Database changed
5 查询数据库trace中有哪些表
mysql> show tables;
6 删除表emp
mysql> drop table emp;
Query OK, 0 rows affected (0.01 sec)
7 删除数据库trace
mysql> drop database trace;
Query OK, 72 rows affected (0.37 sec)
6 导入文件trace.sql (我把trace.sql脚本文件放在了~下)
mysql> source ~/trace.sql;
6 查看当前使用的哪个数据库
mysql> select database();
主从篇
8 查看mysql主机状态和从机状态
查看mysql主机状态---->在主机上执行下述命令:
mysql> show master status;
查看mysql从机状态---->在从机上执行下述命令:
mysql> show slave status\G;
函数篇
myql已经给我们定义好了一些常用的函数,这些常用函数举例如下:
日期和时间常用函数:
1 curdate() 返回当前日期
2 curtime() 返回当前时间
3 now() 返回当前的日期和时间
4 year(date) 返回日期的年份
---- 日期可以是以 xxxx-xx-xx 类型也可以是 xxxx/xx/xx类型
自定义函数篇
1 查看自定义函数功能是否开启
mysql> show variables like '%func%';
如果开启,则显示:
如果未开启,则显示:
自定义函数功能开启命令:
mysql> set global log_bin_trust_function_creators=1;
Query OK, 0 rows affected (0.00 sec)
自定义函数功能关闭命令:
mysql> set global log_bin_trust_function_creators=0;
Query OK, 0 rows affected (0.00 sec)
注意:如果要使用自定义函数功能,则必须开启该功能才可以。
查询语句:
mysql> select m_type,m_status,create_time,busi_id from th_logs_message where m_status != 000 and create_time > '2018-11-20';
+--------+----------+---------------------+---------+
| m_type | m_status | create_time | busi_id |
+--------+----------+---------------------+---------+
| 613 | 3276 | 2018-11-20 10:49:34 | 470 |
| 516 | 3277 | 2018-11-20 10:49:34 | 470 |
| 613 | 3279 | 2018-11-20 10:58:02 | 468 |
| 511 | 3334 | 2018-11-22 10:22:14 | 557 |
| 511 | 3349 | 2018-11-22 10:22:31 | 558 |
| 512 | 3351 | 2018-11-22 13:46:15 | 557 |
| 511 | 3353 | 2018-11-22 13:55:19 | 560 |
| 511 | 3354 | 2018-11-22 14:03:05 | 561 |
| 711 | 3385 | 2018-11-23 13:25:19 | 472 |
| 613 | 3386 | 2018-11-23 13:25:19 | 472 |
| 516 | 3387 | 2018-11-23 13:25:19 | 472 |
| 516 | 3453 | 2018-11-26 10:51:48 | 455 |
| 711 | 3454 | 2018-11-26 10:51:54 | 454 |
| 613 | 3455 | 2018-11-26 10:51:54 | 454 |
| 516 | 3456 | 2018-11-26 10:51:54 | 454 |
+--------+----------+---------------------+---------+
50 rows in set (0.00 sec)
mysql> select m_type,m_status,create_time,busi_id from th_logs_message where m_status = 000 and create_time > '2018-11-20'
-> ;
+--------+----------+---------------------+-------------+
| m_type | m_status | create_time | busi_id |
+--------+----------+---------------------+-------------+
| 515 | 000 | 2018-11-20 09:46:54 | 468 |
| 515 | 000 | 2018-11-20 09:46:56 | 467 |
| 513 | 000 | 2018-11-20 09:55:09 | 545 |
| 611 | 000 | 2018-11-20 10:11:57 | 647 |
| 517 | 000 | 2018-11-20 11:15:46 | 54300000038 |
| 611 | 000 | 2018-11-21 09:44:15 | 656 |
| 511 | 000 | 2018-11-21 09:46:22 | 546 |
| 611 | 000 | 2018-11-23 11:59:40 | 665 |
| 517 | 000 | 2018-11-23 13:19:35 | 56300000029 |
| 611 | 000 | 2018-11-26 11:08:36 | 673 |
| 515 | 000 | 2018-11-26 11:09:39 | 477 |
| 511 | 000 | 2018-11-26 11:10:52 | 566 |
+--------+----------+---------------------+-------------+
154 rows in set (0.01 sec)
mysql> select * from th_logs_message where m_type=516 order by create_time desc limit 0,1;
+------+---------+----------------------------------------------------------------------------------------------------------------------------------+---------+----------+--------+------+---------------------+
| id | busi_id | m_content | from_id | m_status | m_type | ver | create_time |
+------+---------+----------------------------------------------------------------------------------------------------------------------------------+---------+----------+--------+------+---------------------+
| 3473 | 477 | {"data":{"userId":517,"bindId":477},"busiId":"477","v":"1","mid":"5d9864a1-0790-4880-9da5-399e03b25c4b","from":"1","type":"516"} | 1 | 3473 | 516 | 1 | 2018-11-26 11:09:53 |
+------+---------+----------------------------------------------------------------------------------------------------------------------------------+---------+----------+--------+------+---------------------+
1 row in set (0.00 sec)