大约有 41,000 项符合查询结果（耗时：0.0512秒） [XML]
How to create a unique index on a NULL column?
...f uniques" -- NULL is a special value in SQL (similar in many ways to NaN) and needs to be treated accordingly. It's actually a failure in in SQL Server to honor various SQL specifications: here is a link for a request for the "correct implementation" for what it is worth: connect.microsoft.com/SQLS...
Get first key in a (possibly) associative array?
... possibly associative array? My first thought it to just foreach the array and then immediately breaking it, like this:
21 ...
How do I make an HTML text box show a hint when empty?
...ce of any styles, in Chrome this looks like:
You can try demos out here and in HTML5 Placeholder Styling with CSS.
Be sure to check the browser compatibility of this feature. Support in Firefox was added in 3.7. Chrome is fine. Internet Explorer only added support in 10. If you target a browser...
Composer Warning: openssl extension is missing. How to enable in WAMP
...cy management tool on Win7/64 + WampServer 2.2 via the Setup Installer and I am getting the following message:
13 Answe...
Using pip behind a proxy with CNTLM
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Basically, to use CNTLM in any platform, you need to setup your username and hashed password, before using http://127.0.0.1:3128 as a proxy to your parent proxy.
Edit the config and add important information like domain, username, password and parent proxy.
Generate hashed password.
Windows cn...
Fastest way to determine if an integer's square root is an integer
... ~35% faster than your 6bits+Carmack+sqrt code, at least with my CPU (x86) and programming language (C/C++). Your results may vary, especially because I don't know how the Java factor will play out.
My approach is threefold:
First, filter out obvious answers. This includes negative numbers and ...
PowerShell says “execution of scripts is disabled on this system.”
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If you're using Windows Server 2008 R2 then there is an x64 and x86 version of PowerShell both of which have to have their execution policies set. Did you set the execution policy on both hosts?
As an Administrator, you can set the execution policy by typing this into your PowerShell...
Commenting multiple lines in DOS batch file
... DOS Batch file. To test this batch file I need to execute some lines only and want to hide/comment out remaining.
7 Answer...
How to loop through files matching wildcard in batch file
...t of base filenames, for each name 'f' there are exactly two files, 'f.in' and 'f.out'. I want to write a batch file (in Windows XP) which goes through all the filenames, for each one it should:
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How to merge two arrays in JavaScript and de-duplicate items
...ijendra","Singh"];
var array2 = ["Singh", "Shakya"];
// Merges both arrays and gets unique items
var array3 = array1.concat(array2).unique();
This will also preserve the order of the arrays (i.e, no sorting needed).
Since many people are annoyed about prototype augmentation of Array.prototype and ...