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Check if table exists and if it doesn't exist, create it in SQL Server 2008
...read, and you don't have to worry about sys.objects vs. sysobjects vs. sys.all_objects
vs. sys.tables. Basic form:
IF object_id('MyTable') is not null
PRINT 'Present!'
ELSE
PRINT 'Not accounted for'
Of course this will show as "Present" if there is any object present with that name. If yo...
Validate phone number with JavaScript
...he form NXX NXX XXXX where N is a digit 2-9 and X is a digit 0-9. Additionally, area codes and exchanges may not take the form N11 (end with two ones) to avoid confusion with special services except numbers in a non-geographic area code (800, 888, 877, 866, 855, 900) may have a N11 exchange.
So, y...
NSInvocation for Dummies?
...oncept of messages is central to the objective-c philosophy. Any time you call a method, or access a variable of some object, you are sending it a message. NSInvocation comes in handy when you want to send a message to an object at a different point in time, or send the same message several times. N...
How can I sort a dictionary by key?
...89, 4:5, 3:0} to {1:89, 2:3, 3:0, 4:5} ?
I checked some posts but they all use the "sorted" operator that returns tuples.
...
Copy array by value
...5];
let newArray = oldArray.slice();
console.log({newArray});
Basically, the slice() operation clones the array and returns a reference to a new array.
Also note that:
For references, strings and numbers (and not the actual object), slice() copies object references into the new array. Both t...
Get Unix Epoch Time in Swift
...alSince1970)
let preciseMilliseconds = Int(Date().timeIntervalSince1970 * 1_000)
let preciseMicroseconds = Int(Date().timeIntervalSince1970 * 1_000_000) // most likely precise
Unfortunately, however, in the year 2038, 32-bit numbers won't be usable for the Unix timestamp and they'll have to be 64-...
Opening Android Settings programmatically
How can I open settings programmatically?
11 Answers
11
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Get difference between 2 dates in JavaScript? [duplicate]
...day. As for always returning a positive number, that was a feature :) Typically when one talks about the number of days between two dates, that number is positive. If direction matters, just remove the Math.abs().
– TNi
Jul 11 '10 at 22:38
...
How do I work around JavaScript's parseInt octal behavior?
...ust be warned, Number('08.123') will produce 8.123 as its output. If you really want an integer, don't use Number (or pattern-match your input to ensure integers only).
– Jason S
May 11 '09 at 22:22
...
What's a good rate limiting algorithm?
...sages
per = 8.0; // unit: seconds
allowance = rate; // unit: messages
last_check = now(); // floating-point, e.g. usec accuracy. Unit: seconds
when (message_received):
current = now();
time_passed = current - last_check;
last_check = current;
allowance += time_passed * (rate / per);
if (...