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What is the difference between HAVING and WHERE in SQL?
...nt(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than 5 address...
How to stage only part of a new file with git?
...
Whoa, all that update-index and hash-object business seems overly complicated. How about this instead:
git add -N new_file
git add -i
From git help add:
-N, --intent-to-add
Record only the fact that the path will be added ...
How to get an MD5 checksum in PowerShell
...h = [System.BitConverter]::ToString($md5.ComputeHash([System.IO.File]::ReadAllBytes($someFilePath)))
Starting in PowerShell version 4, this is easy to do for files out of the box with the Get-FileHash cmdlet:
Get-FileHash <filepath> -Algorithm MD5
This is certainly preferable since it a...
How to change Vagrant 'default' machine name?
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I found the multiple options confusing, so I decided to test all of them to see exactly what they do.
I'm using VirtualBox 4.2.16-r86992 and Vagrant 1.3.3.
I created a directory called nametest and ran
vagrant init precise64 http://files.vagrantup.com/precise64.box
to generate a...
Launch Bootstrap Modal on page load
I don't know javascript at all. The bootstrap documentation says to
18 Answers
18
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How to run SQL script in MySQL?
...ing '/' instead of '\' worked correctly for me. I got errors when I originally used '/'. This is what worked for me...source C:/Users/macombers/Downloads/midcoast_db.sql;
– Zack Macomber
Oct 3 '14 at 15:09
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Java - get pixel array from image
... is to be able to address pixel (x, y) from the image using int[x][y] . All the methods I have found do not do this (most of them return int[] s).
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Entity Framework: There is already an open DataReader associated with this Command
I am using Entity Framework and occasionally i will get this error.
17 Answers
17
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How do I get a TextBox to only accept numeric input in WPF?
...nly want to allow numbers, dots and dashes.
private static readonly Regex _regex = new Regex("[^0-9.-]+"); //regex that matches disallowed text
private static bool IsTextAllowed(string text)
{
return !_regex.IsMatch(text);
}
If you want to prevent pasting of incorrect data hook up the DataObj...
#include in .h or .c / .cpp?
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True, but doesn't the #ifndef _CALLBACK_H_, on the top of it, prevent the compiler in processing it more than once?
– hytromo
Feb 8 '14 at 12:25
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