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What is the fastest substring search algorithm?
... the performance of most algorithms are: Length? Is there any periodicity? Does the needle contain all unique characters (no repeats)? Or all the same character? Are there a large number of characters in the haystack that never appear in the needle? Is there a chance of having to deal with needles p...
When to use cla(), clf() or close() for clearing a plot in matplotlib?
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Does this work with regards to jupyter? I keep hitting memory errors because figures are not being garbage collected when I rerun a cell in jupyter.
– CMCDragonkai
Mar 5 '17 at 5:35
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Optional query string parameters in ASP.NET Web API
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Yes, but the [FromUri] decorator alone does not appear to support optional parameters.
– John Meyer
May 2 '16 at 21:26
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In C#, how do I calculate someone's age based on a DateTime type birthday?
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This answer does not work with all locales and all ages. Several countries have skipped dates after the birth of current living people, including Russia (1918), Greece (1924) and Turkey (1926).
– Lars D
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Is a view faster than a simple query?
...used instead of the underlying tables and their ordinary indexes. The view does not need to be referenced in the query for the query optimizer to use it during query execution. This allows existing applications to benefit from the newly created indexed views without changing those applications.
Th...
Specifying and saving a figure with exact size in pixels
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Matplotlib doesn't work with pixels directly, but rather physical sizes and DPI. If you want to display a figure with a certain pixel size, you need to know the DPI of your monitor. For example this link will detect that for you.
If yo...
Is an array name a pointer?
...ith an assignment, like this:
a[3] = 9;
Here is a pointer:
int *p;
p doesn't contain any spaces for integers, but it can point to a space for an integer. We can, for example, set it to point to one of the places in the array a, such as the first one:
p = &a[0];
What can be confusing is ...
First-time database design: am I overengineering? [closed]
...n has to be mindful of queries that take seconds to return 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 ...
What are the differences between django-tastypie and djangorestframework? [closed]
...it on their own terms and know that the API really, definitely, absolutely does what the 'documentation' says it does. In the world of integrating with APIs, that fact alone makes DRF the framework to beat.
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Add unique constraint to combination of two columns
...isn't there and no exception was reported.
EDIT here is an example that does exactly what you're asking for, even using the same names as your question, and proves it. You should try it out before assuming the above ideas only treat one column or the other as opposed to the combination...
USE te...