compare

How to compare two tables in postgres

匿名 (未验证) 提交于 2019-12-03 07:36:14
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 want compare two column values which come from two different queries. Can anyone suggest a query which compares two columns in Postgres? 回答1: Well, the easiest to understand--but not necessarily the fastest--is probably something like this. (But you might mean something else by "compare".) -- Values in column1 that aren't in column2. SELECT column1 FROM query1 WHERE column1 NOT IN (SELECT column2 FROM query2); -- Values in column2 that aren't in column1. SELECT column2 FROM query2 WHERE column2 NOT IN (SELECT column1 FROM query1); --

Secure string compare function

…衆ロ難τιáo~ 提交于 2019-12-03 06:44:47
问题 I just came across this code in the HTTP Auth library of the Zend Framework. It seems to be using a special string compare function to make it more secure. However, I don't quite understand the comments. Could anybody explain why this function is more secure than doing $a == $b ? /** * Securely compare two strings for equality while avoided C level memcmp() * optimisations capable of leaking timing information useful to an attacker * attempting to iteratively guess the unknown string (e.g.

QTP vs Selenium - Compare [closed]

℡╲_俬逩灬. 提交于 2019-12-03 06:32:36
Closed . This question is opinion-based. It is not currently accepting answers. Learn more . Want to improve this question? Update the question so it can be answered with facts and citations by editing this post . I have an application/product which is created using .net technologies. This product has a GUI, which connects to a DB using a Web API (SOAP on an application server). Majority of the tests are executed for the values in the DB, while the others may fall into Usability, Performance, etc. As such, 60-70% of the tests to be executed are to verify if the values in the DB are correctly

Comparing an NSDate to [NSDate date]

元气小坏坏 提交于 2019-12-03 06:02:41
I am trying to force a user to select a date in the future with a date picker. I obviously used the compare: method, however, when I do the following code, even if it's the same date as [NSDate date], it tells the executes the if statement. Here is my code: if ([datePicker.date compare:[NSDate date]] == NSOrderedAscending) // If the picked date is earlier than today { UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Hmm, this date is earlier than today" message:@"The date you've selected is earlier than today's date, please pick another" delegate:nil cancelButtonTitle:@"Okay, I'll

How to compare two tarball's content

落爺英雄遲暮 提交于 2019-12-03 05:34:14
问题 I want to tell whether two tarball files contain identical files, in terms of file name and file content, not including meta-data like date, user, group. However, There are some restrictions: first, I have no control of whether the meta-data is included when making the tar file, actually, the tar file always contains meta-data, so directly diff the two tar files doesn't work. Second, since some tar files are so large that I cannot afford to untar them in to a temp directory and diff the

C语言qsort函数总结

一个人想着一个人 提交于 2019-12-03 05:25:08
   前几天在leetcode上刷题,用qsort对二维数组进行排序,发现不会写qsort的比较函数。后面在网上找了几篇博客才弄明白,趁今天有空,对这个做一下总结,主要是以下4个方面: 1、qsort总体介绍 2、qsort应用于一维数组 3、qsort应用于指针数组 4、qsort应用于二维数组 1、qsort总体介绍   函数声明:void qsort(void *base, size_t nitems, size_t size, int (*compare)(const void *, const void*))   参数解释:     base-- 指向要排序的 数组 的第一个元素的指针。注意这里说是数组,所以必须是对连续的内存块进行排序。     nitems-- 由 base 指向的数组中元素的个数     size-- 数组中每个元素的大小,以字节为单位     compare-- 用来比较两个元素的函数。这是qsort最难的一部分了。这里主要要注意以下2点:1、在写compare函数时,你的两个形参必须是const void *型,但是在compare函数内部你又必须将const void *类型的形参转换为实际的类型。这是我最当时最难以理解的一个问题了:我需要转换成什么类型。看了别人的总结才知道,是: 指向数组元素的指针,指向数组元素的指针,指向数组元素的指针

Beyond Compare的几种实用功能

风流意气都作罢 提交于 2019-12-03 05:18:27
《太阳的后裔》大结局已经播完一个多月了,然而这股“太阳”风还在继续发酵着,5曰14日“国名老公”的宋仲基在北京举行粉丝见面会,据悉北京站是此次宋仲基亚洲巡回粉丝见面会的首站,接下来妹子们还有很多可以看偶吧的机会。 但是如果你有堆积如山的文件夹或者文件需要对比,那么去看偶吧可能要成为空想了。现在最新 Beyond Compare 4中文版强势来袭,可以帮助你摆脱枯燥无味的对比工作,使用它可以很方便的对比出两个文件夹或者文件的不同之处,并把相差的每一个字节用颜色加以表示,查看方便。 可能很多朋友对Beyond Compare软件还不太熟悉,接下来小编就和大家分享Beyond Compare的特别之处,体验一下Beyond Compare软件富有人性化的强大功能。 包罗万象的比较对象 软件可以执行的比较会话类型丰富,例如:所有类型的文件、文件夹、压缩包、FTP网站等等光。另外可以通过“会话”菜单中的“会话设置”来设定“常规”和“高级”选项。也可以根据不同的“会话”来定义一系列的过滤设置,并由“会话管理”命令来进行管理,为下次同类型的比较做一劳永逸的准备,十分的人性化。 自定义查看方式 使用Beyond Compare软件对比文件夹和文件时,可以根据个人查询差异的需求,有选择的查看结果。通过点击“视图”菜单,可以对比较结果进行过滤,只看差异的部分或者匹配的部分。但是需要熟知配置中设定的

怎么用Beyond Compare排除空文件

橙三吉。 提交于 2019-12-03 05:18:10
Beyond Compare是一款不可多得的专业文件和文件夹比较工具,软件对比功能强大,操作简单。在我们使用Beyond Compare比较文件夹时,如果对比文件夹包含大量的空文件,通过手动方式来删除文件的话,将会浪费不少时间,接下来本 Beyond Compare教程 就和大家介绍一下,文件夹比较巧妙排除空文件的技巧。 具体操作方式如下所示 步骤一:打开Beyond Compare软件,在主页面选择“文件夹比较”会话,打开会话操作界。分别单击界面左右两侧“打开文件”按钮,选择需要比较的文件夹,如下图所示,对比文件包含空文件。 Beyond Compare文件夹比较会话操作界面图例 步骤二:单击文件夹比较会话菜单栏“会话”按钮,在展开的下拉菜单中选择“会话设置”命令,打开“会话设置—文件夹比较”窗口页面,并切换到“其他过滤”选项卡页面。 步骤三:在打开的“其他过滤“页面中,单击底部”+“按钮,打开”其他过滤“规则设置窗口页面。其中在排除文件下拉菜单中选择”小于“操作,同时输入字节数值为1,单击“确定”按钮关闭窗口。 Beyond Compare会话设置—文件夹比较页面图例 再次单击“确定”按钮,关闭会话设置—文件夹比较窗口页面,返回文件夹比较会话操作界面。如下图图例所示,左右两侧窗格中的空文件均已被排除掉,在状态栏显示提示信息为:小于1字节的文件被排除。 Beyond

Lift compared with Grails

浪尽此生 提交于 2019-12-03 04:58:17
Lift/Scala is getting a lot of attention lately. Having worked with Grails in the past (and finding it quite handy BTW), I'd like to know if there's anyone who has tried both and what's his/her opinion about them. Is one of them better suited for one kind of scenarios whereas the other is better for other kind, or they compete shoulder to shoulder to solve the same problem ? If you're building a CRUD app and you're comfortable with Grails, then stick with it. If any of the following things are priorities for you, then Lift is going to be better: Security -- Lift is more secure than Grails

Compare structures of two databases?

狂风中的少年 提交于 2019-12-03 04:53:22
问题 I wanted to ask whether it is possible to compare the complete database structure of two huge databases. We have two databases, the one is a development database, the other a production database. I've sometimes forgotten to make changes in to the production database, before we released some parts of our code, which results that the production database doesn't have the same structure, so if we release something we got some errors. Is there a way to compare the two, or synchronize? 回答1: What