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Separation of business logic and data access in django
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It seems like you are asking about the difference between the data model and the domain model – the latter is where you can find the business logic and entities as perceived by your end user, the former is where you actually store your data.
Furthermore, I've in...
How can I trim beginning and ending double quotes from a string?
...at said, this smells a bit like that you're trying to invent a CSV parser. If so, I'd suggest to look around for existing libraries, such as OpenCSV.
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How to concatenate two strings to build a complete path
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Except if $part1 can be empty string.
– Tuure Laurinolli
Jan 2 '17 at 14:36
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Parsing JSON from XmlHttpRequest.responseJSON
... with any browser that supports XMLHttpRequest and JSON.
JSONHttpRequest
If you prefer to use responseJSON, but want a more lightweight solution than JQuery, you might want to check out my JSONHttpRequest. It works exactly like a normal XMLHttpRequest, but also provides the responseJSON property. ...
Still Reachable Leak detected by Valgrind
...the functions mentioned in this block are library functions. How can I rectify this memory leak?
5 Answers
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What is process.env.PORT in Node.js?
....PORT || 3000 means: whatever is in the environment variable PORT, or 3000 if there's nothing there.
So you pass that app.listen, or to app.set('port', ...), and that makes your server be able to accept a parameter from the environment what port to listen on.
If you pass 3000 hard-coded to app.lis...
What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
...S vs. LEFT JOIN / IS NULL: MySQL
In a nutshell:
NOT IN is a little bit different: it never matches if there is but a single NULL in the list.
In MySQL, NOT EXISTS is a little bit less efficient
In SQL Server, LEFT JOIN / IS NULL is less efficient
In PostgreSQL, NOT IN is less efficient
In Oracl...
How do you normalize a file path in Bash?
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if you're wanting to chomp part of a filename from the path, "dirname" and "basename" are your friends, and "realpath" is handy too.
dirname /foo/bar/baz
# /foo/bar
basename /foo/bar/baz
# baz
dirname $( dirname /foo/bar...
Trimming a huge (3.5 GB) csv file to read into R
...) for 40 years. In short, it's huge, and it's not going to fit into memory if I try to simply read it.
13 Answers
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C# Convert List to Dictionary
...ey, the second one picks the value.
You can play with it and make values differ from the keys, like this:
var res = list.ToDictionary(x => x, x => string.Format("Val: {0}", x));
If your list contains duplicates, add Distinct() like this:
var res = list.Distinct().ToDictionary(x => x, x...