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Create an index on a huge MySQL production table without table locking
...d or dropped. The CREATE INDEX or DROP INDEX statement only finishes after all transactions that are accessing the table are completed, so that the initial state of the index reflects the most recent contents of the table. Previously, modifying the table while an index is being created or dropped ty...
Measure elapsed time in Swift
...erence in nano seconds (UInt64)
let timeInterval = Double(nanoTime) / 1_000_000_000 // Technically could overflow for long running tests
print("Time to evaluate problem \(problemNumber): \(timeInterval) seconds")
return theAnswer
}
Old answer
For Swift 1 and 2, my function uses NSDate...
Xcode without Storyboard and ARC
...gWithOptions: (NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
TestViewController *test = [[TestViewController alloc] initWithNibName:@"TestViewController" bundle...
Explain Morris inorder tree traversal without using stacks or recursion
... / \
(Y) Z
/ \
C D
(Y) above refers to Y and all of its children, which are omitted for recursion issues. The important part is listed anyway.
Now that the tree has a link back to X, the traversal continues...
A
\
Y
/ \
(A) B
\
X
/ \
(Y)...
Ant task to run an Ant target only if a file exists?
...
Check Using Filename filters like DB_*/**/*.sql
Here is a variation to perform an action if one or more files exist corresponding to a wildcard filter. That is, you don't know the exact name of the file.
Here, we are looking for "*.sql" files in any sub-dire...
Best way to create an empty object in JSON with PHP?
To create an empty JSON object I do usually use:
7 Answers
7
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How to run `rails generate scaffold` when the model already exists?
... using the rails generate option. If you run rails generate -h you can see all of the options available to you.
Rails:
controller
generator
helper
integration_test
mailer
migration
model
observer
performance_test
plugin
resource
scaffold
scaffold_controller
session_migra...
How to create a .NET DateTime from ISO 8601 format
...standard, they seem to be able to parse only a limited subset of it. Especially it is a problem if the string contains time zone specification. (Neither it does for basic ISO8601 formats, or reduced precision formats - however this is not exactly your case.) That is why I make use of custom format s...
How do I change the IntelliJ IDEA default JDK?
...I want IntelliJ IDEA to reflect changes of JAVA_HOME sys variable automatically.
– Ivan_Bereziuk
Nov 16 '17 at 10:48
1
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Why do people write the #!/usr/bin/env python shebang on the first line of a Python script?
...
If you have several versions of Python installed, /usr/bin/env will ensure the interpreter used is the first one on your environment's $PATH. The alternative would be to hardcode something like #!/usr/bin/python; that's ok, but less flexible.
In Unix, an executable f...