sort

本次分享者：辰石，来自阿里巴巴计算平台事业部EMR团队技术专家，目前从事大数据存储以及Spark相关方面的工作。 Spark Shuffle介绍 Smart Shuffle设计 性能分析 Spark Shuffle流程 Spark 0.8及以前 Hash Based Shuffle Spark 0.8.1 为Hash Based Shuffle引入File Consolidation机制 Spark 0.9 引入ExternalAppendOnlyMap Spark 1.1 引入Sort Based Shuffle，但默认仍为Hash Based Shuffle Spark 1.2 默认的Shuffle方式改为Sort Based Shuffle Spark 1.4 引入Tungsten-Sort Based Shuffle Spark 1.6 Tungsten-sort并入Sort Based Shuffle Spark 2.0 Hash Based Shuffle退出历史舞台 总结一下， 就是最开始的时候使用的是 Hash Based Shuffle， 这时候每一个Mapper会根据Reducer的数量创建出相应的bucket，bucket的数量是M x R ，其中M是Map的个数，R是Reduce的个数。这样会产生大量的小文件，对文件系统压力很大，而且也不利于IO吞吐量

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: How i can use python to sort the list format format=["12 sheet","4 sheet","48 sheet","6 sheet", "busrear", "phonebox","train"] like this way format =["4 sheet", "6 sheet", "12 sheet", "48 sheet", "busrear, "phonebox", "train"] edit: If the array is a list of list then how can we do that like this one format=[[1L, u'12 sheet', 0],[2L, u'4 sheet', 0], [3L, u'48 sheet', 0], [4L, u'6 sheet', 0 [5L, u'Busrear', 0], [6L, u'phonebox', 0], [7L, u'train', 0]] 回答1: >>> fmts =["12 sheet","4 sheet","48 sheet","6 sheet", "busrear", "phonebox","train"] >>

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: How to sort boost::unordered_map by value and return only keys in that order ? I have map like boost::unordered_map and I need I need ony list of enums sorted by int values in asc/desc. 回答1: An unordered_map is, as the name implies, inherently not sorted or sortable in-place. You could insert the value pairs into a set that is sorted on the value and get the keys from there (using Boost.Range to make this stuff easier). I use a std::set<T*> to not pay the cost of copying the pair objects. #include <iostream> #include <set> #include

一、查询服务器状态和配置 列出MySQL服务器运行各种状态值： mysql> show global status; 查询MySQL服务器配置信息语句： mysql> show variables; 二、慢查询 mysql> show variables like '%slow%'; +------------------+-------+ | Variable_name | Value | +------------------+-------+ | log_slow_queries | ON | | slow_launch_time | 2 | +------------------+-------+ mysql> show global status like '%slow%'; +---------------------+-------+ | Variable_name | Value | +---------------------+-------+ | Slow_launch_threads | 0 | | Slow_queries | 4148 | +---------------------+-------+　 配置中打开了记录慢查询，执行时间超过2秒的即为慢查询，系统显示有4148个慢查询，你可以分析慢查询日志，找出有问题的SQL语句，慢查询时间不宜设置过长

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have a simple code example @ http://jsbin.com/ukiwo3/edit It has 2 connected lists and a load of bound events. I'm hopeful I've missed something simple as based on http://jqueryui.com/demos/sortable/ Events I think I should see all these events fired when I drag and reorder a question li. At the moment only sort logs to the console. Can anyone tell me whats wrong and how to get the rest to fire? Thanks, Denis 回答1: The events are named differently when binding, for example sortstart instead of start . Look at the list of events on the demo

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Given XML snippet of: <forms> <FORM lob="BO" form_name="AI OM 10"/> <FORM lob="BO" form_name="CL BP 03 01"/> <FORM lob="BO" form_name="AI OM 107"/> <FORM lob="BO" form_name="CL BP 00 02"/> <FORM lob="BO" form_name="123 DDE"/> <FORM lob="BO" form_name="CL BP 00 02"/> <FORM lob="BO" form_name="AI OM 98"/> </forms> I need to sort the FORM nodes by form_name alphabetically so all the forms containing 'AI OM' in the form_name are grouped together and then within that they are in numeric order by the integers (same for other forms). The form_name

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: How do I make this piece of code to order in descending order. This code always gives me the array in ascending order: NSArray *sortedProductsByStyle = [unsortedProducts sortedArrayUsingComparator: ^(Product *p1, Product *p2) { return [p1.productStyle compare:p2.productStyle options:NSNumericSearch]; }]; I thought that using NSOrderedDescending would work but it didn't: NSArray *sortedProductsByStyle = [unsortedProducts sortedArrayUsingComparator: ^(Product *p1, Product *p2) { return [p1.productStyle compare:p2.productStyle options

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I'm trying to override Sort() method in my custom control. When my control contains ListBox and then I override Sort() method, everything works. But when I want my ListBox (1) to be extended by another ListBox (2) , that contains Sort() method, and then add that ListBox (1) to my UserControl, then it sorts too, but isn't using my Sort() method (seems like it doesn't see my Sort(), just normal Sort() from ListBox class). My ListBox (2) contains code: //... public class MyListBox: ListBox { public MyListBox { this.Sorted = true; } // more

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: After years of reading it's time to ask first question :) My problem is that after migrating the code from mySQLi to PDO we have got a problem as it seems PDO adds the apostrophes to the query. PHP code goes like that: $sort = $_GET['sort']; << table column name (mySQL VARCHAR only columns) .... $query = 'SELECT * FROM table WHERE xxx > 0'; $query .= ' ORDER BY :sort ASC ;'; $qry_result= $db->prepare($query); $qry_result->execute(array(':sort'=>$sort)); mysqli version went smoothly but now queries (mysql log file) looks like this: SELECT *

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: How can I randomize the lines in a file using standard tools on Red Hat Linux? I don't have the shuf command, so I am looking for something like a perl or awk one-liner that accomplishes the same task. 回答1: And a Perl one-liner you get! perl - MList :: Util - e 'print List::Util::shuffle <>' It uses a module, but the module is part of the Perl code distribution. If that's not good enough, you may consider rolling your own. I tried using this with the -i flag ("edit-in-place") to have it edit the file. The documentation suggests it