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How to subtract 30 days from the current datetime in mysql?
... * FROM table
WHERE exec_datetime BETWEEN DATE_SUB(NOW(), INTERVAL 30 DAY) AND NOW();
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-add
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How do I send a JSON string in a POST request in Go
I tried working with Apiary and made a universal template to send JSON to mock server and have this code:
4 Answers
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Difference between left join and right join in SQL Server [duplicate]
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Select * from Table1 left join Table2 ...
and
Select * from Table2 right join Table1 ...
are indeed completely interchangeable. Try however Table2 left join Table1 (or its identical pair, Table1 right join Table2) to see a difference. This query should give you mo...
How can I avoid running ActiveRecord callbacks?
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This solution is Rails 2 only.
I just investigated this and I think I have a solution. There are two ActiveRecord private methods that you can use:
update_without_callbacks
create_without_callbacks
You're going to have to use send to call these methods. examples:
p = Person.ne...
How many and which are the uses of “const” in C++?
...y obscure to me, one of these is const . You can use it in so many places and with so many different effects that is nearly impossible for a beginner to come out alive. Will some C++ guru explain once forever the various uses and whether and/or why not to use them?
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Is Javascript a Functional Programming Language?
Just because functions are first class objects, there are closures, and higher order functions, does Javascript deserve to be called a Functional Programming language? The main thing I think it lacks is Pure Functions, and it doesn't 'feel' like other functional languages, like lisp (although thats...
Is key-value observation (KVO) available in Swift?
...mework can help you accomplish what you wanted, rather than using KVO
Yes and no. KVO works on NSObject subclasses much as it always has. It does not work for classes that don't subclass NSObject. Swift does not (currently at least) have its own native observation system.
(See comments for how to ...
visual studio not remembering open documents & startup project
For the past week, something has changed about my VS solution, and I havent found a setting to fix it yet.
16 Answers
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“unrecognized selector sent to instance” error in Objective-C
I created a button and added an action for it, but as soon as it invoked, I got this error:
38 Answers
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Why don't structs support inheritance?
...rt inheritance is because of arrays.
The problem is that, for performance and GC reasons, arrays of value types are stored "inline". For example, given new FooType[10] {...}, if FooType is a reference type, 11 objects will be created on the managed heap (one for the array, and 10 for each type ins...