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What is the format specifier for unsigned short int?
...ntf" short ints because they are automatically promoted to ints (just like chars).
– Alexey Frunze
Jan 2 '12 at 11:00
2
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How to alter SQL in “Edit Top 200 Rows” in SSMS 2008
...008 Management Studio, when I right click on a database table and choose " Select Top 100 Rows ", I can then e.g. easily add a "ORDER BY " statement to the SQL. That works fine .
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Why is there no tuple comprehension in Python?
...because tuple syntax and parenthesis are ambiguous
– Charles Salvia
Jun 5 '13 at 13:14
21
The dif...
Select multiple columns in data.table by their numeric indices
How can we select multiple columns using a vector of their numeric indices (position) in data.table ?
5 Answers
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How to find the Number of CPU Cores via .NET/C#?
...ors:
foreach (var item in new System.Management.ManagementObjectSearcher("Select * from Win32_ComputerSystem").Get())
{
Console.WriteLine("Number Of Physical Processors: {0} ", item["NumberOfProcessors"]);
}
Cores:
int coreCount = 0;
foreach (var item in new System.Management.ManagementObjec...
Strings as Primary Keys in SQL Database [closed]
... Also keep in mind that there's often a very big difference between a CHAR and a VARCHAR when doing index comparisons
– Tom H
Feb 5 '09 at 20:42
7
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Reshaping data.frame from wide to long format
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Here is another example showing the use of gather from tidyr. You can select the columns to gather either by removing them individually (as I do here), or by including the years you want explicitly.
Note that, to handle the commas (and X's added if check.names = FALSE is not set), I am also us...
Finding duplicate values in MySQL
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Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
select、poll、epoll之间的区别总结[整理] - C/C++ - 清泛网 - 专注C/C++及内核技术
select、poll、epoll之间的区别总结[整理]select，poll，epoll都是IO多路复用的机制。I O多路复用就通过一种机制，可以监视多个描述符，一旦某个描述符就绪（一般是读就绪或者写就绪...select，poll，epoll都是IO多路复用的机制。I/O多路...
Ruby Arrays: select(), collect(), and map()
...re, to check the :qty key, you'd do something like the following:
details.select{ |item| item[:qty] != "" }
That will give you all items where the :qty key isn't an empty string.
official select documentation
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