MySQL笔记（三）由txt文件导入数据

改编自学校实验，涉及一些字符集相关的问题。

索引

建库
导入数据
最终脚本

建库

create.sql

DROP DATABASE IF EXISTS orderdb;
CREATE DATABASE orderdb;
USE orderdb;

CREATE TABLE employee (
        employee_no VARCHAR(8),
        employee_name VARCHAR(10),
        sex CHAR(1),
        birthday DATE,
        address VARCHAR(50),
        telephone VARCHAR(20),
        hiredate DATE COMMENT '聘用日期',
        department VARCHAR(30),
        headship VARCHAR(10) COMMENT '职务',
        salary DECIMAL(8,2),

        PRIMARY KEY(employee_no)

)       ENGINE=INNODB DEFAULT CHARSET=utf8;

CREATE TABLE customer (
        customer_no VARCHAR(9),
        customer_name VARCHAR(40),
        telephone VARCHAR(20),
        address VARCHAR(40),
        zip VARCHAR(6),

        PRIMARY KEY(customer_no)

)       ENGINE=INNODB DEFAULT CHARSET=utf8;

CREATE TABLE product (
        product_no VARCHAR(9),
        product_name VARCHAR(40),
        product_class VARCHAR(20),
        product_price DECIMAL(7,2),

)       ENGINE=INNODB DEFAULT CHARSET=utf8;

        order_no VARCHAR(12),
        customer_no VARCHAR(9),
        saler_no VARCHAR(8),
        order_date DATE,
        order_sum DECIMAL(9,2),
        invoiceno CHAR(10) COMMENT '发票号码',

        PRIMARY KEY (order_no),

        FOREIGN KEY (customer_no)
                REFERENCES customer(customer_no)

)       ENGINE=INNODB DEFAULT CHARSET=utf8;

CREATE TABLE order_detail (
        order_no VARCHAR(12),
        product_no VARCHAR(9),
        quantity INT,
        price DECIMAL(7,2),

        PRIMARY KEY (order_no, product_no),

        FOREIGN KEY (order_no)
                REFERENCES order_master(order_no),
        FOREIGN KEY (product_no)
                REFERENCES product(product_no)

)       ENGINE=INNODB DEFAULT CHARSET=utf8;

Linux 环境下运行脚本：

root@xkfx:~/sql-exercise# readlink -f create.sql 
/root/sql-exercise/create.sql # 复制这个路径
root@xkfx:~/sql-exercise# mysql -uroot -p
mysql > SOURCE /root/sql-exercise/create.sql # 运行脚本

导入数据

在 Linux 环境下或许需要修改 txt 的编码格式：

root@xkfx:~/sql-exercise# iconv -f gb18030  -t utf8 customer.txt -o customer.txt

并且待导入的 txt 文件必须放在特定目录下，查看特定目录：

mysql> show variables like '%secure%';
+------------------+-----------------------+
| Variable_name    | Value                 |
+------------------+-----------------------+
| secure_auth      | OFF                   |
| secure_file_priv | /var/lib/mysql-files/ |
+------------------+-----------------------+

如上所示 /var/lib/mysql-files/ 就是特定的目录。导入数据：

LOAD DATA INFILE 'file_path' INTO TABLE table_name
FIELDS TERMINATED BY 'xxx'
LINES TERMINATED BY 'xxxx'

示范如下：

mysql> USE orderdb
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> LOAD DATA INFILE '/var/lib/mysql-files/customer.txt' INTO TABLE customer
    -> FIELDS TERMINATED BY ','
    -> LINES TERMINATED BY '
';
Query OK, 10 rows affected, 10 warnings (0.00 sec)
Records: 10  Deleted: 0  Skipped: 0  Warnings: 10

这个时候试着 SELECT 一下 customer 中的数据，有很大概率是乱码的，这个时候不要着急，你需要重新设定字符集再来一遍：

SHOW VARIABLES LIKE "%char%"; # 显示字符集的设定情况
SET character_set_database=utf8; # 像这样，把不是 utf8 的设定为 utf8
SET NAMES 'utf8';

SOURCE /root/sql-exercise/create.sql

LOAD DATA INFILE '/var/lib/mysql-files/customer.txt' INTO TABLE customer
FIELDS TERMINATED BY ','
LINES TERMINATED BY '
';

补充：平时创建表的时候要保证 ↓

以及：

CREATE TABLE xxxxx (
  
)    ENGINE=INNODB DEFAULT CHARSET=utf8;

才不容易出现乱码。

最终脚本

为了方便起见，只需要把相应文件放在特定位置，修改一下脚本中的路径，最后运行最终脚本就可以了：

populate.sql

LOAD DATA INFILE '/var/lib/mysql-files/customer.txt' INTO TABLE customer
FIELDS TERMINATED BY ','
LINES TERMINATED BY '
';

LOAD DATA INFILE '/var/lib/mysql-files/employee.txt' INTO TABLE employee
FIELDS TERMINATED BY ','
LINES TERMINATED BY '
';

LOAD DATA INFILE '/var/lib/mysql-files/ordermaster.txt' INTO TABLE order_master
FIELDS TERMINATED BY ','
LINES TERMINATED BY '
';

LOAD DATA INFILE '/var/lib/mysql-files/product.txt' INTO TABLE product
FIELDS TERMINATED BY ','
LINES TERMINATED BY '
';

LOAD DATA INFILE '/var/lib/mysql-files/orderdetail.txt' INTO TABLE order_detail
FIELDS TERMINATED BY ','
LINES TERMINATED BY '
';

最终脚本.sql

SET character_set_database = utf8; 
SET character_set_server = utf8;
SET NAMES 'utf8';
SHOW VARIABLES LIKE "%char%"; 
SOURCE /root/sql-exercise/create.sql
SOURCE /root/sql-exercise/populate.sql

mysql> SOURCE /root/sql-exercise/orderdb.sql