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数据库表的操作
数据表（table），是一种二维表格，类似于execel，用来存储真正的数据。
创建表格
#语法结构
create table [if not exists] t_name (# 定义表结构字段名称1 类型 [约束条件],字段2 类型 [约束条件],……字段n 类型 [约束条件]
);/**创建一个用户表用户的姓名用户的年龄用户的性别用户的地址用户的电话
**/
create table t_user (id int,name varchar(50),age int,gender char(5),address varchar(255),tel char(11)
);# 查询表中的数据
select * from t_name;# 插入数据
insert into t_name values(1, "duum", 16, '女', "四川成都", "110");
mysql> show tables;
+----------------------+
| Tables_in_db_test |
+----------------------+
| t_name |
+----------------------+
1 row in set (0.00 sec)mysql> select * from t_name;
Empty set (0.00 sec)mysql> describe t_name;
+---------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| id | int | YES | | NULL | |
| name | varchar(50) | YES | | NULL | |
| age | int | YES | | NULL | |
| gender | char(5) | YES | | NULL | |
| address | varchar(255) | YES | | NULL | |
| tel | char(11) | YES | | NULL | |
+---------+--------------+------+-----+---------+-------+
6 rows in set (0.00 sec)mysql> show create table t_name;
+--------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table|
+--------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| t_name | CREATE TABLE `t_name` (`id` int DEFAULT NULL,`name` varchar(50) DEFAULT NULL,`age` int DEFAULT NULL,`gender` char(5) DEFAULT NULL,`address` varchar(255) DEFAULT NULL,`tel` char(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci |
+--------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)mysql> show create table t_name\G
*************************** 1. row ***************************Table: t_name
Create Table: CREATE TABLE `t_name` (`id` int DEFAULT NULL,`name` varchar(50) DEFAULT NULL,`age` int DEFAULT NULL,`gender` char(5) DEFAULT NULL,`address` varchar(255) DEFAULT NULL,`tel` char(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
1 row in set (0.00 sec)mysql> insert into t_name values(1, "小度", 16, '女', "四川成都", "120");
Query OK, 1 row affected (0.01 sec)mysql> select * from t_name;
+------+-----------+------+--------+--------------+------+
| id | name | age | gender | address | tel |
+------+-----------+------+--------+--------------+------+
| 1 | 小度 | 16 | 女 | 四川成都 | 120 |
+------+-----------+------+--------+--------------+------+
1 row in set (0.00 sec)
⚠️ 注意：查询sql时，如果结果较多，查看不方便，则可以反正查询的结果，在sql后面加上
\G
删除表格
drop table [if exists] t_name;