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What is an ORM, how does it work, and how should I use one? [closed]
... case with a pseudo language:
You have a book class, you want to retrieve all the books of which the author is "Linus". Manually, you would do something like that:
book_list = new List();
sql = "SELECT book FROM library WHERE author = 'Linus'";
data = query(sql); // I over simplify ...
while (row ...
Django: How do I add arbitrary html attributes to input fields on a form?
... earlier to modify 3 fields: ``` for field_name in ['image', 'image_small', 'image_mobile']: field = self.fields.get(field_name) field.widget.attrs['data-file'] = 'file' ```
– Stuart Axon
Jun 6 '14 at 11:59
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How to implement the factory method pattern in C++ correctly
...
First of all, there are cases when
object construction is a task complex
enough to justify its extraction to
another class.
I believe this point is incorrect. The complexity doesn't really matter. The relevance is what does. I...
Calling C/C++ from Python?
...e Boost Python Library is a framework for interfacing Python and
C++. It allows you to quickly and seamlessly expose C++ classes
functions and objects to Python, and vice-versa, using no special
tools -- just your C++ compiler. It is designed to wrap C++ interfaces
non-intrusively, so that y...
Is there a null-coalescing (Elvis) operator or safe navigation operator in javascript?
...e expression is null, but also when it's undefined, false, 0, or the empty string.
– Cameron
Jul 7 '11 at 16:41
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What's the difference between lists and tuples?
.... A list on the other hand could be used to store multiple locations. Naturally one might want to add or remove locations from the list, so it makes sense that lists are mutable. On the other hand it doesn't make sense to add or remove items from an existing location - hence tuples are immutable.
T...
How do I get my Python program to sleep for 50 milliseconds?
...rity, CPU load avg, available memory, and a plethora of other factors make all calls imprecise. The busier the system is, the higher the imprecision.
– David
Jan 28 '19 at 18:44
2...
Understanding typedefs for function pointers in C
...es' code which had typedefs for pointers to functions with arguments. I recall that it took me a while to get around to such a definition while trying to understand a numerical algorithm written in C a while ago. So, could you share your tips and thoughts on how to write good typedefs for pointers t...
Is there an online name demangler for C++? [closed]
...d implementations of demanglers are horribly buggy and insecure. They basically only work on mangled names that the same platform produced, but may run into high complexity or flat out memory errors on general inputs.
– Kerrek SB
Mar 29 '17 at 0:07
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How to create a multi-tenant database with shared table structures?
...ibrary/Force.com_Multitenancy_WP_101508.pdf
They have 1 huge table w/ 500 string columns (Value0, Value1, ... Value500). Dates and Numbers are stored as strings in a format such that they can be converted to their native types at the database level. There are meta data tables that define the shap...