Home Database Mysql Tutorial MySQL常用数据表操作SQL

MySQL常用数据表操作SQL

Jun 07, 2016 pm 04:32 PM
mysql sql Commonly used operate data sheet Program development

作为程序开发员, 经常要导入导出一些数据, 今天就把我导入导出数据的一些SQL分享一下: 下文中所有的测试语句数据表明都用 tablename 1. 导出表结构 show create table tablename; 2. 导出一个表的数据到外部文件 select * into outfile '/tmp/data.txt' f

作为程序开发员, 经常要导入导出一些数据, 今天就把我导入导出数据的一些SQL分享一下:

下文中所有的测试语句数据表明都用 tablename

1. 导出表结构

show create table tablename;
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2. 导出一个表的数据到外部文件

select * into outfile '/tmp/data.txt' from tablename;
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输出的文件格式默认每条记录以 \n (换行符)分割, 每个字段之间以 \t (TAB键)分割, 可以自定义分隔符, 请查手册

3. 把表里边的数据导入到另外的数据表

当两个数据表的字段一样且顺序相同, 可以不用列举每一个字段:

insert into tablename1 select * from tablename2
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如果字段不同, 或者

insert into tablename1 (column1, column2) select column3 as column1, column4 as column2 from tablename2;
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不管是连表查询, group limit 等操作生成的结果也可以存储到另外的数据表中, 不过你要使用别名保证数据表字段相对应

insert into tablename1(column1, column2) select a.column3 as column1 , b.column4 as column2 from tablename2 a, tablename3 b on a.column4=b.column4   limit100
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4. 从文件中导入数据到数据表

load data infile '/tmp/data.txt' into table tablename. 
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默认的外部文件, 记录分隔符是 \n (换行符), 字段的分隔符是 \t (Tab键) , 当然也可以自己指定分隔符, 具体的参数查手册!

5. 直接创建表并把查询结果保存到新的表

create table tablename1 select * from table2 
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后边的SQL语句也支持 group, limit, join, union 等操作, 不在演示, 自己动手尝试

 OK ,  数据表操作常用SQL就这些了, 请继续关注我的博客: http://www.phpv5.com  , 有问题我们共同探讨h

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