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Unique Constraint in Entity Framework Code First
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As far as I can tell, there's no way to do this with Entity Framework at the moment. However, this isn't just a problem with unique constraints... you may want to create indexes, check constraints, and possibly triggers and other constructs too. Here's a simple pattern you can use with your...
How to find out how many lines of code there are in an Xcode project?
...not to use such information for managerial measurement or employee benchmarking purposes. ;)
15 Answers
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Python dict how to create key or append an element to key?
I have an empty dictionary. Name: dict_x
It is to have keys of which values are lists.
5 Answers
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How to implement a Map with multiple keys? [duplicate]
I need a data structure which behaves like a Map,
but uses multiple (differently-typed) keys to access its values.
(Let's not be too general, let's say two keys)
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Converting timestamp to time ago in PHP e.g 1 day ago, 2 days ago…
...timestamp of the format 2009-09-12 20:57:19 and turn it into something like 3 minutes ago with PHP.
30 Answers
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Database: To delete or not to delete records
I don't think I am the only person wondering about this. What do you usually practice about database behavior? Do you prefer to delete a record from the database physically? Or is it better to just flag the record with a "deleted" flag or a boolean column to denote the record is active or inactive?
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Java Reflection Performance
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Yes - absolutely. Looking up a class via reflection is, by magnitude, more expensive.
Quoting Java's documentation on reflection:
Because reflection involves types that are dynamically resolved, certain Java virtual machine optimizations can...
Inserting image into IPython notebook markdown
I am starting to depend heavily on the IPython notebook app to develop and document algorithms. It is awesome; but there is something that seems like it should be possible, but I can't figure out how to do it:
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How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...te a single expression that returns these two dictionaries, merged (i.e. taking the union). The update() method would be what I need, if it returned its result instead of modifying a dictionary in-place.
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Is there a fixed sized queue which removes excessive elements?
...there are two open implementations available (this answer is quite old, folks!), see this answer for details.
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