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Entity Framework 4 Single() vs First() vs FirstOrDefault()
... times while the same context is alive.
Single() - when you expect exactly one item to be returned by a query. This will throw an exception if the query does not return exactly one item.
SingleOrDefault() - when you expect zero or one items to be returned by a query (i.e. you are not sure if an item...
Database development mistakes made by application developers [closed]
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1. Not using appropriate indices
This is a relatively easy one but still it happens all the time. Foreign keys should have indexes on them. If you're using a field in a WHERE you should (probably) have an index on it. Such indexes should often cover multiple columns based on the q...
When to use which design pattern? [closed]
...design patterns very much, but I find it difficult to see when I can apply one. I have read a lot of websites where design patterns are explained. I do understand the most of them, but I find it difficult to recognize a pattern in my own situations.
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RegEx to make sure that the string contains at least one lower case char, upper case char, digit and
What is the regex to make sure that a given string contains at least one character from each of the following categories.
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Different ways of clearing lists
Is there any reason to do anything more complicated than one of these two lines when you want to clear a list in Python?
8 ...
What is the difference between concurrency, parallelism and asynchronous methods?
... they do have different definitions: Concurrent = Existing, happening, or done at the same time. Parallel = of or pertaining to the apparent or actual performance of more than one operation at a time, by the same or different devices. As you can see parallel does not necessarily mean concurrent but ...
Is it possible to install APK file if more than one emulators/devices are connected [duplicate]
...to multiple emulator by giving any specific name ?
Actually i have to test one apk file in to many device. and for that i have started many device. I know how to install it. if the all device are open then it will not get install. So is there any alternate to install that apk file by giving any spec...
One line ftp server in python
Is it possible to have a one line command in python to do a simple ftp server? I'd like to be able to do this as quick and temporary way to transfer files to a linux box without having to install a ftp server. Preferably a way using built in python libraries so there's nothing extra to install.
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In C/C++ what's the simplest way to reverse the order of bits in a byte?
... creating the lookup table does still require another solution. (Of course one might do it by hand, but that's error-prone and time-consuming…)
– Arkku
Apr 8 '10 at 19:52
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Reading output of a command into an array in Bash
...acters like *, ?, [...].
To get the output of a command in an array, with one line per element, there are essentially 3 ways:
With Bash≥4 use mapfile—it's the most efficient:
mapfile -t my_array < <( my_command )
Otherwise, a loop reading the output (slower, but safe):
my_array=()
wh...