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How do I check to see if a value is an integer in MySQL?
...e REGEXP operator, matching the string to a regular expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
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Select first 4 rows of a data.frame in R
How can I select the first 4 rows of a data.frame :
5 Answers
5
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Differences between fork and exec
..." functions to create the child process
execvp (argv[0], const_cast<char**>(argv));
} else { // This is the Parent Process
//Continue executing parent process
}
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Change name of iPhone app in Xcode 4
...veryone:
1.In the project contents pane at left, click the Folder icon.
2.Select the top-level blue line representing the project.
3.If you don't have the Inspector pane (right pane) open, click the button to enable it. This is the third button in the "View" toolbar towards the upper right corner...
How do I check if an index exists on a table field in MySQL?
...
Try:
SELECT * FROM information_schema.statistics
WHERE table_schema = [DATABASE NAME]
AND table_name = [TABLE NAME] AND column_name = [COLUMN NAME]
It will tell you if there is an index of any kind on a certain column wi...
The type or namespace name 'DbContext' could not be found [closed]
... @Chris Dickinson, right click on the References item in the project and select Add Reference.... Then in the .NET tab, select System.Data.Entity. And if you want to use NuGet, right click on the References item and then select Add Library Package Reference... and in the Online tab, search for Ent...
Heroku/GoDaddy: send naked domain to www [closed]
....com to www.yourdomain.com.
Here's how.
Within Account Manager, select My Domain Names
Select the domain name that you want to manage
In the green box, select Change Where Domain Points
Select Advanced DNS, then Continue
First, edit the A Records by selecting Edit A Records
F...
How to link to specific line number on github
...s://github.com/git/git/blob/master/README#L18
If you want multiple lines selected, simply hold down the shift key and click a second line number, like line 20. Looks like this:
And now your browser's URL looks like this:
https://github.com/git/git/blob/master/README#L18-L20
Here's the import...
How do you open an SDF file (SQL Server Compact Edition)? [closed]
...t intuitive:
Open SQL Server Management Studio, or if it's running select File -> Connect Object Explorer...
In the Connect to Server dialog change Server type to SQL Server Compact Edition
From the Database file dropdown select < Browse for more...>
Open your SDF file.
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Best way to test if a generic type is a string? (C#)
..., UInt16, Int32, UInt32, Int64, UInt64, Single, Double, Decimal, DateTime, Char, and String, so you can check for primitive types using this. More info on "Generic Type Checking".
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