<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[ace15452的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/ace15452</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; ace15452]]></copyright><item><title><![CDATA[mysql相关]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059284</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059284</guid><author>ace15452</author><pubDate>Tue, 13 Aug 2019 14:35:00 +0800</pubDate><description><![CDATA[1)查看当前所处的数据库：
select database();
2)查看表的一些状态信息，比如最后一次更新日期
show table status from your_db like 'your_table';
或者
select *
from   information_schema.tables
where  table_schema = 'your_db'
   and tabl...]]></description><category></category></item><item><title><![CDATA[curl 整理]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059282</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059282</guid><author>ace15452</author><pubDate>Thu, 18 Jul 2019 11:07:00 +0800</pubDate><description><![CDATA[curl
(1)curl url: 查看网页源码
curl -o[--output] filename url: 把网页保存下来,相当于wget
culr -O url: url必须具体到某个文件
curl -L 网址:自动跳转
curl -i url: 显示头信息,-I只显示头信息
curl -v url: 显示通信过程
curl --trace outputfile url: 更详细...]]></description><category></category></item><item><title><![CDATA[linux 拆分文件]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059280</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059280</guid><author>ace15452</author><pubDate>Tue, 02 Apr 2019 14:43:00 +0800</pubDate><description><![CDATA[split [OPTION]... [INPUT [PREFIX]] :根据行或者大小拆分文件
split file_name :默认把文件file_name拆分成xaa,xab,xac,......
默认每1000行拆分一次，默认的“PREFIX”为“x”，默认后缀为长度为2的字母，即aa,ab,ac,ad,ae,.....
-a：后缀的长度
-b ：指定拆分后文件的大小
-d : 后...]]></description><category></category></item><item><title><![CDATA[Python中的排序方法]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059279</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059279</guid><author>ace15452</author><pubDate>Fri, 01 Mar 2019 13:12:00 +0800</pubDate><description><![CDATA[1 list.sort
list.sort(key=None, reverse=False)
该方法只能用于list。就地排序，原来的list被修改。key的用法见下文。reverse控制降序还是生序，默认是升序（key为None的前提下。如果key指定了顺序，则reverse=True时采取相反顺序）
print(a)
a.sort()
print(a)
a.sort(reverse=...]]></description><category></category></item><item><title><![CDATA[about python]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059283</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059283</guid><author>ace15452</author><pubDate>Mon, 14 Jan 2019 11:38:00 +0800</pubDate><description><![CDATA[显示dir目录下的所有项目名称（包括目录名和文件名）
os.listdir(dir)
路径拼接（使用目录分隔符os.sep拼接）
os.path.join(dir, filename)
返回绝对路径
os.path.abspath(path)
返回路径的dirname和basename：
if path=/foo/bar.txt, dirname=/foo, basename=/bar....]]></description><category></category></item><item><title><![CDATA[vim 常用命令]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059276</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059276</guid><author>ace15452</author><pubDate>Wed, 19 Dec 2018 14:31:00 +0800</pubDate><description><![CDATA[查找替换

1 :%s/search_for_this/replace_with_this/

上面的命令只替换一次，替换第一次查找到的目标search_for_this：要查找的目标replace_with_this：替换成该单词

1 :%s/search_for_this/replace_with_this/c   - confirm each replace

c...]]></description><category></category></item><item><title><![CDATA[Clickhouse DDL&DML]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059273</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059273</guid><author>ace15452</author><pubDate>Thu, 25 Oct 2018 10:48:00 +0800</pubDate><description><![CDATA[（1）添加列：

alter table [db.]table_name add column column_name [type] [default_expr] [after name_after]

type：类型
default_expr：默认值
after name_agter：把新列添加在指定列后面
(2)删除列：

alter table [db.]tabl...]]></description><category></category></item><item><title><![CDATA[Hive窗口函数]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059271</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059271</guid><author>ace15452</author><pubDate>Tue, 04 Sep 2018 19:42:00 +0800</pubDate><description><![CDATA[窗口函数(Windowing functions)
1. lead
lead(col,n,DEFAULT)：统计窗口内往下第n行。n可选，默认为1，default为默认值（即往下第n行位null时返回default）。可选，默认null。
SELECT a, LEAD(a) OVER (PARTITION BY b ORDER BY C) FROM T;
返回a，以及对应窗口内对...]]></description><category></category></item><item><title><![CDATA[linux nohup & 简单使用]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059281</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059281</guid><author>ace15452</author><pubDate>Tue, 04 Sep 2018 17:50:00 +0800</pubDate><description><![CDATA[线上通常nohup配合&amp;启动程序，同时免疫SIGINT和SIGHUP信号，从而保证程序在后台稳定运行

&amp;
1.后台运行，输出默认到屏幕
2.免疫SIGINT信号，比如Ctrl+c不会杀死程序
3.响应SIGHUP信号，关闭session发送SIGHUP信号，程序关闭
4.通过jobs和fg重新转到前台运行


nohup
1.不挂断运行，输出默...]]></description><category></category></item><item><title><![CDATA[Hive DDL&DML]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059270</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059270</guid><author>ace15452</author><pubDate>Tue, 21 Aug 2018 10:34:00 +0800</pubDate><description><![CDATA[1.删除分区

ALTER TABLE table_name DROP IF EXISTS PARTITION(dt='20180101')

如果是外部表，记得rm对应文件
2.添加分区

ALTER TABLE table_name ADD IF NOT EXISTS PARTITION(dt='20180101')

3.删除表

DROP TABLE tab...]]></description><category></category></item><item><title><![CDATA[HDFS命令]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059253</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059253</guid><author>ace15452</author><pubDate>Tue, 31 Jul 2018 10:36:00 +0800</pubDate><description><![CDATA[1.查看客户端默认的Block大小

hdfs getconf -confKey dfs.blocksize


2.查看指定文件的Block大小

hadoop fs -stat %o hdfs://localhost/user/harsh/file.txt


3.把本地文件上传到服务器

hadoop dfs -copyFromLocal &lt;local...]]></description><category></category></item><item><title><![CDATA[HiveServer2后台运行]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059238</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059238</guid><author>ace15452</author><pubDate>Mon, 23 Jul 2018 16:05:00 +0800</pubDate><description><![CDATA[nohup hive --service hiveserver2 &amp;


　或者直接：

nohup hiveserver2 &amp;


　　

转载于:https://www.cnblogs.com/vdvvdd/p/9355172.html]]></description><category></category></item><item><title><![CDATA[[ Hive ] Warning: Value had a \n character in it.]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059236</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059236</guid><author>ace15452</author><pubDate>Tue, 05 Jun 2018 10:08:00 +0800</pubDate><description><![CDATA[执行Hive sql时报错：Warning: Value had a \n character in it.

原因及解决：
可能某条语句后面落了分号。我的是某个set语句后面丢了分号。

转载于:https://www.cnblogs.com/vdvvdd/articles/9138296.html...]]></description><category></category></item><item><title><![CDATA[我的瑞士军刀]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059251</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059251</guid><author>ace15452</author><pubDate>Wed, 23 May 2018 14:48:00 +0800</pubDate><description><![CDATA[1PicPick
一个全功能的屏幕截图工具

转载于:https://www.cnblogs.com/vdvvdd/p/9076871.html]]></description><category></category></item><item><title><![CDATA[Linux下清空文件的常用方法]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059249</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059249</guid><author>ace15452</author><pubDate>Wed, 20 Sep 2017 09:45:00 +0800</pubDate><description><![CDATA[1. 本人用的最多，感觉也是最方便的：

&gt; filename.log 

2. 　

: &gt; filename.log


3.

cat /dev/null &gt; filename.log


　

转载于:https://www.cnblogs.com/vdvvdd/p/7559915.html...]]></description><category></category></item><item><title><![CDATA[nc的简单使用]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059247</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059247</guid><author>ace15452</author><pubDate>Mon, 04 Sep 2017 16:02:00 +0800</pubDate><description><![CDATA[1.传输文件：
目的主机监听
nc -l监听端口&lt;未使用端口&gt;&gt;要接收的文件名
nc -l 6666 &gt; filename.tar

源主机发起请求
nc目的主机ip目的端口&lt;要发送的文件
nc10.102.xx.xx 6666 &lt; ./filename.tar

转载于:https://www.cnblo...]]></description><category></category></item><item><title><![CDATA[Go语言string，int，int64 ,float转换]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059245</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059245</guid><author>ace15452</author><pubDate>Thu, 20 Jul 2017 14:37:00 +0800</pubDate><description><![CDATA[(1)int转string

s := strconv.Itoa(i)
等价于s := strconv.FormatInt(int64(i), 10)

(2)int64转string

i := int64(123)
s := strconv.FormatInt(i, 10)

第二个参数为基数，可选2~36
注：对于无符号整形，可以使用FormatUint(i ...]]></description><category></category></item><item><title><![CDATA[Go 时间相关]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059234</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059234</guid><author>ace15452</author><pubDate>Wed, 28 Jun 2017 10:23:00 +0800</pubDate><description><![CDATA[&gt;获取当前时间：

t := time.Now()



&gt;获取当天开始、结束时间：

tm1 := time.Date(t.Year(), t.Month(), t.Day(), 0, 0, 0, 0, t.Location())
tm2 := time.Date(t.Year(), t.Month(), t.Day(), 23, 59, 59, 0, ...]]></description><category></category></item><item><title><![CDATA[CentOS 命令]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059230</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059230</guid><author>ace15452</author><pubDate>Tue, 20 Jun 2017 09:40:00 +0800</pubDate><description><![CDATA[1.防火墙相关：

systemctl stop firewalld.service #停止firewall
systemctl disable firewalld.service #禁止firewall开机启动systemctl enable firewalld.service #开机自启动service firewalld status #查看防火墙状态service fire...]]></description><category></category></item><item><title><![CDATA[Centos 修改源]]></title><link>https://blog.youkuaiyun.com/ace15452/article/details/102059227</link><guid>https://blog.youkuaiyun.com/ace15452/article/details/102059227</guid><author>ace15452</author><pubDate>Wed, 31 May 2017 13:57:00 +0800</pubDate><description><![CDATA[1首先备份原来的配置文件：

mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup

2下载对应版本repo文件, 放入/etc/yum.repos.d/
3生成缓存：

yum clean all
yum makecache



转载于:https://www....]]></description><category></category></item></channel></rss>