<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[caoaobin的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/caoaobin</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; caoaobin]]></copyright><item><title><![CDATA[关于hivesql报错]]></title><link>https://blog.youkuaiyun.com/caoaobin/article/details/134944844</link><guid>https://blog.youkuaiyun.com/caoaobin/article/details/134944844</guid><author>caoaobin</author><pubDate>Tue, 12 Dec 2023 11:19:49 +0800</pubDate><description><![CDATA[解决方法：重启集群，重启hadoop、hive、zookeeper。我发现我的namenode挂掉了，所以重启就解决了。]]></description><category></category></item><item><title><![CDATA[python常见面试题]]></title><link>https://blog.youkuaiyun.com/caoaobin/article/details/134010460</link><guid>https://blog.youkuaiyun.com/caoaobin/article/details/134010460</guid><author>caoaobin</author><pubDate>Tue, 24 Oct 2023 13:52:22 +0800</pubDate><description><![CDATA[python常见面试题，题目来源千锋，答案来源千锋+chatgtp]]></description><category></category></item><item><title><![CDATA[MySQL TIMESTAMPDIFF函数简介]]></title><link>https://blog.youkuaiyun.com/caoaobin/article/details/123413496</link><guid>https://blog.youkuaiyun.com/caoaobin/article/details/123413496</guid><author>caoaobin</author><pubDate>Thu, 10 Mar 2022 22:39:59 +0800</pubDate><description><![CDATA[MySQL TIMESTAMPDIFF函数简介
TIMESTAMPDIFF(unit,begin,end); 

TIMESTAMPDIFF函数返回begin-end的结果，其中begin和end是DATE或DATETIME表达式。
TIMESTAMPDIFF函数允许其参数具有混合类型，例如，begin是DATE值，end可以是DATETIME值。 如果使用DATE值，则TIMESTAMPDIFF函数将其视为时间部分为“00:00:00”的DATETIME值。
unit参数是确定(end-begin)的结果]]></description><category></category></item><item><title><![CDATA[查找员工在入职以来的薪水涨幅情况]]></title><link>https://blog.youkuaiyun.com/caoaobin/article/details/123409053</link><guid>https://blog.youkuaiyun.com/caoaobin/article/details/123409053</guid><author>caoaobin</author><pubDate>Thu, 10 Mar 2022 19:20:28 +0800</pubDate><description><![CDATA[查找员工在入职以来的薪水涨幅情况
drop table if exists  `employees` ; 
drop table if exists  `salaries` ;

CREATE TABLE `employees` (
`emp_no` int(11) NOT NULL,
`birth_date` date NOT NULL,
`first_name` varchar(14) NOT NULL,
`last_name` varchar(16) NOT NULL,
`gender` char(1]]></description><category></category></item><item><title><![CDATA[关于dateadd与datediff的使用方法]]></title><link>https://blog.youkuaiyun.com/caoaobin/article/details/123409027</link><guid>https://blog.youkuaiyun.com/caoaobin/article/details/123409027</guid><author>caoaobin</author><pubDate>Thu, 10 Mar 2022 19:19:38 +0800</pubDate><description><![CDATA[关于dateadd与datediff的使用方法
DATEADD函数计算一个日期通过给时间间隔加减来获得一个新的日期，DATEDIFF函数计算两个日期之间的小时、天、周、月、年等时间间隔总数。
1、SQL Server DATEADD() 函数
DATEADD() 函数在日期中添加或减去指定的时间间隔。
语法
DATEADD(datepart,number,date)

date 参数是合法的日期表达式。number 是您希望添加的间隔数；对于未来的时间，此数是正数，对于过去的时间，此数是负数。
datepa]]></description><category></category></item><item><title><![CDATA[MYSQL笔记（全）__窗口函数]]></title><link>https://blog.youkuaiyun.com/caoaobin/article/details/123391557</link><guid>https://blog.youkuaiyun.com/caoaobin/article/details/123391557</guid><author>caoaobin</author><pubDate>Thu, 10 Mar 2022 01:40:00 +0800</pubDate><description><![CDATA[FIRST 阶段一
一、MYSQL中查询五子句
select * from 数据表       ① where子句
						② group by 分组子句
						③ having子句
						④ order by子句
						⑤ limit子句

注意事项：①②③④⑤五子句是SQL中最重要的五个子句，而且其顺序不能颠倒
二、查询语句
select * from tb_student;				
select id,name,address from tb_student;

1、回顾wher]]></description><category></category></item><item><title><![CDATA[MYSQL学习DAY1笔记]]></title><link>https://blog.youkuaiyun.com/caoaobin/article/details/123288360</link><guid>https://blog.youkuaiyun.com/caoaobin/article/details/123288360</guid><author>caoaobin</author><pubDate>Sat, 05 Mar 2022 00:57:32 +0800</pubDate><description><![CDATA[这是我的第一天的MYSQL学习笔记]]></description><category></category></item></channel></rss>