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Storing time-series data, relational or non?
...Device, Metric, DateTime)
The Id column does nothing, it is totally and completely redundant.
An Id column is never a Key (duplicate rows, which are prohibited in a Relational database, must be prevented by other means).
The Id column requires an additional Index, which obviously impedes th...
First-time database design: am I overengineering? [closed]
...turn data. Not only does a report server function have more tolerance for complex and lengthy queries, but the strategies to improve performance are much different.
For example, in a transaction based application environment your performance improvement options might include refactoring your sto...
Should operator
...p < > <= >=
These operators should return a bool as they are comparing two objects of the same type. It is usually easiest to define these operators as part of the class. This is because a class is automatically a friend of itself so objects of type Paragraph can examine each other (ev...
Differences between Octave and MATLAB? [closed]
...ide whether to learn GNU Octave or Matlab. I know that they have a lot in common , but it isn't clear to me how similar the syntax is or even the data structures are. The above link shows several examples where they are syntactically similar or identical, is this true for the whole language?
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How to use sed to replace only the first occurrence in a file?
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Type Checking: typeof, GetType, or is?
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All are different.
typeof takes a type name (which you specify at compile time).
GetType gets the runtime type of an instance.
is returns true if an instance is in the inheritance tree.
Example
class Animal { }
class Dog : Animal { }
void PrintTypes(Animal a) {
Console.WriteLine(a...
How can I selectively merge or pick changes from another branch in Git?
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You use the cherry-pick command to get individual commits from one branch.
If the change(s) you want are not in individual commits, then use the method shown here to split the commit into individual commits. Roughly speaking, you use git rebase -i ...
Accessing dict keys like an attribute?
...ute correctly raises AttributeError instead of KeyError
Supports [Tab] autocompletion (e.g. in jupyter & ipython)
Cons:
Methods like .keys() will not work just fine if they get overwritten by incoming data
Each AttrDict instance actually stores 2 dictionaries, one inherited and another one in ...
Android activity life cycle - what are all these methods for?
...lways followed by onStart()
onStart():
Called when the activity is becoming visible to the user. Followed by
onResume() if the activity comes to the foreground.
onResume():
Called when the activity will start interacting with the user. At this
point your activity is at the top of the...
Function pointers, Closures, and Lambda
...omehow and after a search online I didn't find really any analysis of this comparison.
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