1. desc 命令
格式: desc tablename columnname
例子:
desc `table` `mid`
desc `table` ‘%abc%‘
2. show columns 命令
格式: show columns from tablename like columnname
例子:
show columns from `table` like ‘mid‘
show columns from `table` like ‘%abc%‘
3. describe 命令
格式: describe tablename columnname
describe 相當于 show columns from
例子:
describe `table` `mid`
describe `table` ‘%abc%‘mysql判断字段是否存在的方法
原文：http://www.jb51.net/article/46149.htm
