SQL学习笔记:基础教程

SQL语法

  • 在表中选择列
    select 列名 from 表名
  • 选择所有列
    select * from 表名
  • 返回唯一值
    select distinct 列名 from 表名
  • where
    select * from 表名 where city = 'beijng'
    select * from 表名 where year = 1993
  • OR AND
    select * from 表名 where city = 'beijing' and year=1993
  • ORDER BY
    select * from tablename ORDER BY col1 DESC, col2 ASC
  • 插入新的行
    insert into tablename (col1, col2) values ('q', 'w')
  • 更新数据
    update tablename set col1 = 'newdata', col2 = 'newdata' where col='zhi'
  • 删除行
    delete from tablename where col = 'data'
    delete * from tablename
posted @ 2018-01-22 15:53  嘻呵呵  阅读(285)  评论(0编辑  收藏  举报