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mysql执行外部sql
如果有一个外部sql文件名叫"mydb.sql";是要创建一个表，假定数据库为"mydb";
1.mysql 未登录：
Java代码
mysql -uroot -p1234 //绝对路径，单引号可以无
mysql -uroot -p1234 mydb //直接进入mydb，结果一样，如果sql文件没有use 声明，可以
2.mysql 已登录：
Java代码
source /root/桌面/abc.sql;
//source 后面跟上绝对路径，可以
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