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Difference between two dates in MySQL
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SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01');
-- result: 22:00:59, the difference in HH:MM:SS format
SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00');
-- result: 79259 the differenc...
How can I define a composite primary key in SQL?
...for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because to use a composite index requires using all the keys from th...
How to do this using jQuery - document.getElementById(“selectlist”).value
In jQuery, what is the equivalent to document.getElementById("selectlist").value ?
6 Answers
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How to find the key of the largest value hash?
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You can use the select method if you want the key value pair returned:
hash.select {|k,v| v == hash.values.max }
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How do you detect Credit card type based on number?
...: before processing a cardholder PAN, strip any whitespace and punctuation characters from the input. Why? Because it’s typically much easier to enter the digits in groups, similar to how they’re displayed on the front of an actual credit card, i.e.
4444 4444 4444 4444
is much easier to ent...
How do I set the selected item in a comboBox to match my string using C#?
..." and my comboBox contains test1 , test2 , and test3 . How do I set the selected item to "test1"? That is, how do I match my string to one of the comboBox items?
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Installing Apple's Network Link Conditioner Tool
...per.apple.com/download/more/?q=Additional%20Tools
Install the dmg file, select hardware from installer
select Network Link conditioner prefpane
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In Xcode, how to suppress all warnings in specific source files?
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Select your target and show Build Phases. Then enter the name of the file in the search box, and you should see it listed in the Compile Sources phase. Double-click in the Compiler Flags column for that file and enter -w to t...
Only parameterless constructors and initializers are supported in LINQ to Entities
... where nalTmp.idDziecko == idDziec
select new Payments
{
Imie = nalTmp.Dziecko.Imie,
Nazwisko = nalTmp.Dziecko.Nazwisko,
Nazwa= ...
What does a type followed by _t (underscore-t) represent?
... could cause some confusion. As well as size_t, the C89 standard defines wchar_t, off_t, ptrdiff_t, and probably some others I've forgotten. The C99 standard defines a lot of extra types, such as uintptr_t, intmax_t, int8_t, uint_least16_t, uint_fast32_t, and so on. These new types are formally d...