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How to wait for 2 seconds?
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The documentation for WAITFOR() doesn't explicitly lay out the required string format.
This will wait for 2 seconds:
WAITFOR DELAY '00:00:02';
The format is hh:mi:ss.mmm.
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Check if a value is an object in JavaScript
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@Tresdin The best way is to run Object.prototype.toString.call(yourVar), being yourVar what you need to inspect. In case of arrays, Object.prototype.toString.call([1,2]) returns [object Array]
– Jose Rui Santos
Feb 25 '16 at 9:48
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What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...eading ‘+’ nor exponential
notation is recognized. To compare
such strings numerically, use the
--general-numeric-sort (-g) option.
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How to declare an array in Python?
... contains references to items. Also, underlying array is created with some extra space.
Consequences of this are:
random access is really cheap (arr[6653] is same to arr[0])
append operation is 'for free' while some extra space
insert operation is expensive
Check this awesome table of operation...
Shortcuts in Objective-C to concatenate NSStrings
Are there any shortcuts to ( stringByAppendingString: ) string concatenation in Objective-C, or shortcuts for working with NSString in general?
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What's the difference between ASCII and Unicode?
...t their language (to support "é", in French, for example). Just using one extra bit doubled the size of the original ASCII table to map up to 256 characters (2^8 = 256 characters). And not 2^7 as before (128).
10000010 -> é (e with acute accent - 130)
10100000 -> á (a with acute accent - 16...
Reasons for using the set.seed function
...set the seed (or choose a seed to pass into set.seed) based on a character string. For example you could have students use their name as the seed then each student has a unique dataset but the instructor can also create the same datasets for grading.
– Greg Snow
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Getting raw SQL query string from PDO prepared statements
Is there a way to get the raw SQL string executed when calling PDOStatement::execute() on a prepared statement? For debugging purposes this would be extremely useful.
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Is there a way to detect if an image is blurry?
...d
% focus value.
% Method, is the focus measure algorithm as a string.
% see 'operators.txt' for a list of focus
% measure methods.
% ROI, Image ROI as a rectangle [xo yo width heigth].
% if an empty argument is passed, the whole
% image is ...
MySQL Error 1215: Cannot add foreign key constraint
... @www.jensolsson.se You are correct, if the PK includes one or more string columns then they must use the same character set and collation. In this specific case the PK was an INT so the character set of the table and/or columns was not relevant.
– Ike Walker
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