学习总结基本的MySQL数据库导入导出操作 1 表tt的格式: CREATE TABLE `tt` ( `ind` int NOT NULL auto_increment, `name`
学习总结基本的MySQL数据库导入导出操作
1 表tt的格式:
CREATE TABLE `tt` (
`ind` int NOT NULL auto_increment,
`name` char(100) default NULL,
PRIMARY KEY (`ind`)
)
2 文件d.txt的内容示例:
1,a
2,b
3,c
3 导入命令:
mysql> load data infile 'd.txt' into table tt
-> fields terminated by','
-> lines terminated by'\r\n'
注意的地方:
1)、文件可以使用绝对路径如'c:/d.txt',否则请将文件放在数据库根目录中
2)、因为字段之间用了逗号隔开,所以必须fields terminated by',',否则导入失败
3)、因为Winsows中行以“\r\n”隔开,所以必须lines terminated by'\r\n',
如果不设置这个参数,也可导入成功,但是会多导入一个“\r”控制字符,可能在可视化
MySQL工具中看不出字段异样,但是在MySQL命令行中显示会明显混乱。
4)、如果表tt非空,,且文件中的ind值在表中有重复,会提示错误,并导入失败。
只导入name字段,文件d.txt的内容:
a
b
c
mysql> load data infile 'd.txt' into table tt
-> lines terminated by'\r\n'
-> (name);
load data 命令还支持更复杂的文本格式、文件编码等,可参考官方文档。
5 导出到数据到windows文本文件时,为了方便查看,也需要相同的设置
mysql> select * from tt into outfile 'd.txt'
-> fields terminated by','
-> lines terminated by'\r\n'

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