select into outfile导出数据sql语句
select into outfile命令是mysql中一种用来导出数据的一个常用的命令,下面我来介绍select into outfile的用法,有需要的朋友可参考。
mysql管理数据当然可以很方便的导出数据,但是当数据量很大是,phpmyadmin很可能会发生执行超时,其实很容易用select into outfile解决!
SELECT...INTO OUTFILE语句的主要作用是让您可以非常快速地把一个表转储到服务器机器上。如果您想要在服务器主机之外的部分客户主机上创建结果文件,您不能使用SELECT...INTO OUTFILE。在这种情况下,您应该在客户主机上使用比如“mysql –e "SELECT ..." > file_name”的命令,来生成文件。
SELECT...INTO OUTFILE是LOAD DATA INFILE的补语;用于语句的exort_options部分的语法包括部分FIELDS和LINES子句,这些子句与LOAD DATA INFILE语句同时使用
如下:(将数据库wordpress中的wp_posts表导出到D盘)
代码如下 | 复制代码 |
select * into outfile 'd:data.txt' from wp_posts |
需要注意的是:使用select into outfile语句,必须要有执行权限,路径必须存在,否则使用当前数据库目录,
例2
代码如下 | 复制代码 |
表结构及测试数据 `id` INT(1) NOT NULL AUTO_INCREMENT PRIMARY KEY, `name` VARCHAR(10) NOT NULL, `add` VARCHAR(20) CHARACTER SET gbk NOT NULL )ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO `tab`(`name`,`add`) VALUES ('中文', '这列不会乱码'), ('汉字', '这列不会乱码');
SELECT * FROM `tab`;
+----+------+--------------+ | id | name | add | +----+------+--------------+ | 1 | 中文 | 这列不会乱码 | | 2 | 汉字 | 这列不会乱码 | +----+------+--------------+ |
代码
代码如下 | 复制代码 |
在 INTO OUTFILE 中使用变量 |
上面的代码会在C盘下生成“sql_当前时间.txt”的文件,避免INTO OUTFILE文件已存在错误
注:直接在命令行中SELECT显示无乱码,但使用 INTO OUTFILE 导出后有乱码,此时必须修改显示乱码的列的字符集

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