mysql常用指令

:~# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 3
Server version: 5.7.27-0ubuntu0.16.04.1 (Ubuntu)

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Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.

mysql>
mysql> ls
->
->
->
-> ^C^C^C
mysql>
mysql>
mysql>
mysql>
mysql>
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| django |
| mysql |
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.00 sec)

mysql>
mysql>
mysql> use django;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql>
mysql> show tables;
+------------------+
| Tables_in_django |
+------------------+
| ranking |
+------------------+
1 row in set (0.00 sec)

mysql>
mysql> use table ranking;
ERROR 1049 (42000): Unknown database 'table'
mysql> use ranking;
ERROR 1049 (42000): Unknown database 'ranking'
mysql> alter table ranking add hash varchar(50);
Query OK, 0 rows affected (0.03 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql>
mysql>
mysql>
mysql> show tables;
+------------------+
| Tables_in_django |
+------------------+
| ranking |
+------------------+
1 row in set (0.00 sec)

mysql> show columns from ranking;
+----------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+--------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| username | varchar(100) | NO | | NULL | |
| mark | int(11) | NO | | NULL | |
| hash | varchar(50) | YES | | NULL | |
+----------+--------------+------+-----+---------+----------------+
4 rows in set (0.00 sec)

mysql>
mysql>
mysql>
mysql> show columns from ranking;

create table ranking (
id int primary key auto_increment,
username varchar(100) not null default '',
mark int not null default 0,
hash varchar(50) ,
date date,
imgpath varchar(50)
);

INSERT INTO ranking(username, mark, date, imgpath, hash) VALUES ('小春', 81.918, '2019-10-27 07:30:39', '小春_81.918_20191027073039.jpg', 'cd9f9fcf1f7d7d3f');