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Is there any difference between GROUP BY and DISTINCT
...nce (in SQL Server, at least). Both queries use the same execution plan.
http://sqlmag.com/database-performance-tuning/distinct-vs-group
Maybe there is a difference, if there are sub-queries involved:
http://blog.sqlauthority.com/2007/03/29/sql-server-difference-between-distinct-and-group-by-dis...
What is the difference between typeof and instanceof and when should one be used vs. the other?
...; // true
typeof function() {} == 'function'; // true
Use instanceof for complex built in types:
/regularexpression/ instanceof RegExp; // true
typeof /regularexpression/; // object
[] instanceof Array; // true
typeof []; //object
{} instanceof Object; // true
typeof {}; // object
And the las...
When should null values of Boolean be used?
...y means that your Boolean was never created.
You might find this useful: http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/6-b14/java/lang/Boolean.java
A null Boolean reference should only be used to trigger similar logic to which you have any other null reference. Using it f...
Java : How to determine the correct charset encoding of a stream
...ave used this library, similar to jchardet for detecting encoding in Java:
http://code.google.com/p/juniversalchardet/
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How can I efficiently select a Standard Library container in C++11?
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
How do I read image data from a URL in Python?
...tatus code while fetching an image from a URL. Instead, I had to resort to http.client to get the image.
– MSS
Aug 8 '19 at 6:46
...
What is the exact meaning of Git Bash?
...files from the days of DOS and early versions of Windows.
REFERENCES:
https://en.wikipedia.org/wiki/Bash_(Unix_shell)
https://en.wikipedia.org/wiki/Windows_PowerShell
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App Inventor 2 字典 vs 列表：同样存数据，性能差了10倍？ - App应用开发 ...
...ttps://www.fun123.cn</a><br>- 社区讨论：<a href="https://bbs.tsingfun.com" target="_blank">https://bbs.tsingfun.com</a><br>
How can you find and replace text in a file using the Windows command-line environment?
...%str%
Script Output:
teh cat in teh hat
the cat in the hat
ref: http://www.dostips.com/DtTipsStringManipulation.php#Snippets.Replace
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Maven Install on Mac OS X
...
OS X prior to Mavericks (10.9) actually comes with Maven 3 built in.
If you're on OS X Lion, you won't have java installed by default. Just run java by itself and it'll prompt you to install it.
Assuming qualifications are met, run mvn -version and see some ou...