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How to unit test an object with database queries

I've heard that unit testing is "totally awesome", "really cool" and "all manner of good things" but 70% or more of my files involve database access (some read and some write) and I'm not sure how to write a unit test for these files. ...
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Pandas - How to flatten a hierarchical index in columns

..., but leaves behind column names which are difficult to access programmatically and are not queriable – dmeu Jun 29 '17 at 8:53 1 ...
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How can i query for null values in entity framework?

...g this bug! For backwards compatibility, it will be opt-in - you need manually enable a setting to make entry == value work. No word yet on what this setting is. Stay tuned! Edit 2: According to this post by the EF team, this issue has been fixed in EF6! Woohoo! We changed the default be...
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best way to get the key of a key/value javascript object

... If you want to get all keys, ECMAScript 5 introduced Object.keys. This is only supported by newer browsers but the MDC documentation provides an alternative implementation (which also uses for...in btw): if(!Object.keys) Object.keys = function...
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How does “cat

... This is called heredoc format to provide a string into stdin. See https://en.wikipedia.org/wiki/Here_document#Unix_shells for more details. From man bash: Here Documents This type of redirection instructs the shell to read...
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Installing Python 3 on RHEL

I'm trying to install python3 on RHEL using the following steps: 19 Answers 19 ...
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Which characters are valid in CSS class names/selectors?

What characters/symbols are allowed within the CSS class selectors? I know that the following characters are invalid , but what characters are valid ? ...
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What does enumerate() mean?

...ieving that; one using itertools.count() to do the counting, the other manually counting in a generator function: from itertools import count def enumerate(it, start=0): # return an iterator that adds a counter to each element of it return zip(count(start), it) and def enumerate(it, sta...
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Is the C# static constructor thread safe?

... { mutex.WaitOne(); return instance; } // Each call to Acquire() requires a call to Release() public static void Release() { mutex.ReleaseMutex(); } } share | ...
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Is it better to use C void arguments “void foo(void)” or not “void foo()”? [duplicate]

...either the count is communicated nor the types of what is needed - as with all function declarations that use identifier lists. So the caller has to know the types and the count precisely before-hand. So if the caller calls the function giving it some argument, the behavior is undefined. The stack c...