目录概述语法详解数学运算表达式Shell变量变量分类环境变量Shell内部变量自定义变量：定义、赋值自定义变量：引用、修改、删除自定义变量：设置只读Shell命令替换：将命令的结果赋值变量Shell变量表达式shell测试判断
I have this piece of SQL that is being fed to Mysql. CREATE TABLE pn_history( member INT, action INT,
加载中,请稍侯......