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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 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
...
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...
Does MongoDB's $in clause guarantee order
...the results
{ "$sort": { "weight": 1 } }
])
So that would be the expanded form. What basically happens here is that just as the array of values is passed to $in you also construct a "nested" $cond statement to test the values and assign an appropriate weight. As that "weight" value reflects t...
ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
...relationships involve a parent table that holds the
central data values, and a child table with identical values pointing
back to its parent. The FOREIGN KEY clause is specified in the child
table.
It will reject any INSERT or UPDATE operation that attempts to create
a foreign key value...
What is the use for IHttpHandler.IsReusable?
I'm writing a IHttpHandler and I'll need to implement a IsReusable property. When I look at the MSDN documentation it says:
...
How do you get assembler output from C/C++ source in gcc?
... the preprocessor (cpp) over helloworld.c, perform the initial compilation and then stop before the assembler is run.
By default this will output a file helloworld.s. The output file can be still be set by using the -o option.
gcc -S -o my_asm_output.s helloworld.c
Of course this only works if y...
Container View Controller Examples [closed]
...roller Class Reference . I feel I need a little more information than that and an example implementation would be nice. Google has turned up nothing at all.
...
Fastest way to find second (third…) highest/lowest value in vector or column
R offers max and min, but I do not see a really fast way to find another value in the order, apart from sorting the whole vector and then picking a value x from this vector.
...
How can you speed up Eclipse?
... Indigo (3.7.2) SR2 loads in 4 seconds, in Kepler SR2 (4.3.2) in 7 seconds and in Luna (4.4.0) in 10 seconds. All are Java EE bundles. Newer versions have more bundled plugins, but still the trend is obvious. (by "same" workspace I mean: same (additionally installed) plugins used, same projects chec...