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What is the maximum value for an int32?
...correctly in the mirror. Otherwise you'll see 746,384,741,2 which is wrong and would be embarrassing.
– Larry S
Apr 21 '16 at 20:20
127
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How to call a function from a string stored in a variable?
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Also see my answer below if you are dealing with classes and methods. I didn't expect what I found.
– Chris K
Jan 28 '13 at 23:16
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C++ performance vs. Java/C#
My understanding is that C/C++ produces native code to run on a particular machine architecture. Conversely, languages like Java and C# run on top of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because ...
ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
...relationships involve a parent table that holds the
central data values, and a child table with identical values pointing
back to its parent. The FOREIGN KEY clause is specified in the child
table.
It will reject any INSERT or UPDATE operation that attempts to create
a foreign key value...
Make function wait until element exists
...you can put your function. The interval solution is really a bad solution and should be used only if nothing else works.
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MySQL Query GROUP BY day / month / year
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GROUP BY YEAR(record_date), MONTH(record_date)
Check out the date and time functions in MySQL.
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Are there strongly-typed collections in Objective-C?
I'm new to Mac/iPhone programming and Objective-C. In C# and Java we have "generics", collection classes whose members can only be of the type declared. For example, in C#
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What is SuppressWarnings (“unchecked”) in Java?
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Sometimes Java generics just doesn't let you do what you want to, and you need to effectively tell the compiler that what you're doing really will be legal at execution time.
I usually find this a pain when I'm mocking a generic interface, but there are other examples too. It's usually wor...
How do I clone a Django model instance object and save it to the database?
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Just change the primary key of your object and run save().
obj = Foo.objects.get(pk=<some_existing_pk>)
obj.pk = None
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: h...
How to verify Facebook access token?
... edited Jan 13 '16 at 19:11
AndHeiberg
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answered May 29 '13 at 20:07
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