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What is a proper naming convention for MySQL FKs?
... users(user_id);
I try to stick with the same field names in referencing and referenced tables, as in user_id in the above example. When this is not practical, I also append the referenced field name to the foreign key name.
This naming convention allows me to "guess" the symbolic name just by l...
Convert a python dict to a string and back
...but this data needs to be saved at some point during the program execution and loaded back into the dictionary object when the program is run again.
How would I convert a dictionary object into a string that can be written to a file and loaded back into a dictionary object? This will hopefully suppo...
What is the difference between a static and a non-static initialization code block
...static from the initializer block, it then becomes an instance initializer and so int a is initialized at construction.
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“Automatic” vs “Automatic (Delayed start)”
...tically starting a Windows service on Windows startup. One is Automatic , and the other is Automatic (Delayed start) . What is the difference between these two in detail?
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Debugging in Clojure? [closed]
...
There's also dotrace, which allows you to look at the inputs and outputs of selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (fib 3)
TRACE t4426: | (fib 2)
T...
Named routes _path vs _url
...st of the time.
_url helpers provide an absolute path, including protocol and server name. I've found that I mainly use these in emails when creating links to the app on the server. They should mainly be used when providing links for external use. (Think email links, RSS, and things like the copy a...
psycopg2: insert multiple rows with one query
...", x) for x in tup)
cur.execute("INSERT INTO table VALUES " + args_str)
and 2 minutes when using this method:
cur.executemany("INSERT INTO table VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s)", tup)
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What is the JavaScript version of sleep()?
...esolve or reject).
Compatibility
promises are supported in Node v0.12+ and widely supported in browsers, except IE
async/await landed in V8 and has been enabled by default since Chrome 55 (released in Dec 2016)
it landed in Node 7 in October 2016
and also landed in Firefox Nightly in November ...
Keep file in a Git repo, but don't track changes
...t solution to do this. First change the file you do not want to be tracked and use the following command:
git update-index --assume-unchanged FILE_NAME
and if you want to track the changes again use this command:
git update-index --no-assume-unchanged FILE_NAME
git-update-index documentation...
How do I use the conditional operator (? :) in Ruby?
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It is the ternary operator, and it works like in C (the parenthesis are not required). It's an expression that works like:
if_this_is_a_true_value ? then_the_result_is_this : else_it_is_this
However, in Ruby, if is also an expression so: if a then b ...