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Reset the database (purge all), then seed a database
Is there a rake command to wipe out the data in the database tables?
6 Answers
6
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How many random elements before MD5 produces collisions?
... quintillion 374 quadrillion 607 trillion 431 billion 768 million 211 thousand 456.
However if you keep all the hashes then the probability is a bit higher thanks to birthday paradox. To have a 50% chance of any hash colliding with any other hash you need 264 hashes. This means that to get a collis...
How can I round a number in JavaScript? .toFixed() returns a string?
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It returns a string because 0.1, and powers thereof (which are used to display decimal fractions), are not representable (at least not with full accuracy) in binary floating-point systems.
For example, 0.1 is really 0.100000000000000005551115123125782702118...
versionCode vs versionName in Android Manifest
I had my app in the android market with version code = 2 and version name = 1.1
10 Answers
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Select multiple records based on list of Id's with linq
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Contains() will handle that equality check on each id value if you use it as I've written in the answer. You don't have to explicitly write == anywhere when you're trying to compare the items of one set (the array) against another (the datab...
Unable to show a Git tree in terminal
...witchcollective.com's old article, 30 June 2009 , has the following inputs and outputs
6 Answers
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How do I get the list of keys in a Dictionary?
I only want the Keys and not the Values of a Dictionary.
9 Answers
9
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AWS S3: how do I see how much disk space is using
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AWS Cloudwatch now has a metric for bucket size and number of objects that is updated daily. About time! aws.amazon.com/blogs/aws/…
– cudds
Jul 28 '15 at 23:13
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How to delete multiple values from a vector?
I have a vector like: a = c(1:10) and I need to remove multiple values, like: 2, 3, 5
8 Answers
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Get push notification while App in foreground iOS
...tificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void)
{
completionHandler([.alert, .badge, .sound])
}
iOS 10, Swift 2.3 :
@available(iOS 10.0, *)
func userNotificationCenter(center: UNUse...