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MySQL写入数据通常用insert语句,如
insert into person values(张三,20),(李四,21),(王五,70)…;
但有时为了更快速地插入大批量数据或交换数据,需要从文本中导入数据或导出数据到文本。
一、 建立测试表,准备数据
首先建立一个用于测试的表示学生信息的表,字段有id、姓名、年龄、城市、薪水。Id和姓名不
能为空。
create table person(
id int not null auto_increment,
name varchar(40) not null,
city varchar(20),
salary int,
primary key(id)
)engine=innodb charset=gb2312;
创建表截图如下:
接着写一个用于导入的文本文件:c:/data.txt。
张三 31 北京 3000
李四 25 杭州 4000
王五 45 /N 4500
小明 29 天津 /N
每一项之间用Tab键进行分隔,如果该字段为NULL,则用/N表示。
二、 导入数据
输入命令,进行导入。
load data local infile “c:/data.txt”
into table person(name,age,city,salary);
导入数据截图如下:
其中local表示本地。执行后,可以看到NULL数据也被正确地导入。
三、 导出数据
现在将这个表导出为文本文件:c:/data_out.txt。
select name,age,city,salary
into outfile “c:/data_out.txt”
lines terminated by “/r/n”
from person;
导出数据截图如下:
其中lines terminated by “/r/n”表示每一行(即每一条记录)用/r/n分隔,/r/n是window系
统的换行符。导出的data_out.txt与data.txt的内容完全一样。
四、 运行环境
Windows vista home basic
MySQL 5.1.34-community
五、 注意
字段之间的分隔和记录(行)之间的分隔默认是/t(即Tab)和/n。但可以改变,如:
FIELDS TERMINATED BY ',' --字段用,进行分隔
LINES TERMINATED BY ';' --记录用; 进行分隔
另外要注意其它操作系统的换行符与windows可能不相同。bitsCN.com

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