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Storing money in a decimal column - what precision and scale?
...or domain expert about accounting rules which may be applicable: GAAP, EU, etc. I vaguely recall some EU intra-state transfers with explicit rules for rounding to five decimal places, therefore using DECIMAL(p, 6) for storage. Accountants generally seem to favour four decimal places.
PS Avoid SQL...
Best practices with STDIN in Ruby?
...ARGF is your friend when it comes to input; it is a virtual file that gets all input from named files or all from STDIN.
ARGF.each_with_index do |line, idx|
print ARGF.filename, ":", idx, ";", line
end
# print all the lines in every file passed via command line that contains login
ARGF.each do...
How do I find the location of my Python site-packages directory?
...ib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and see python -m site --help for explanations.
Hint: Running pip list --user or pip freeze -...
AWS MySQL RDS vs AWS DynamoDB [closed]
... for a fair while now and I'm comfortable with its structure & SQL Queries etc.
4 Answers
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Determine if variable is defined in Python [duplicate]
...ime? This is not always obvious because (1) the variable could be conditionally set, and (2) the variable could be conditionally deleted. I'm looking for something like defined() in Perl or isset() in PHP or defined? in Ruby.
...
Comparing strings with == which are declared final in Java
...nal and initialized with a compile-time constant expression (§15.28), is called a constant variable.
Also from JLS §15.28 - Constant Expression:
Compile-time constant expressions of type String are always "interned" so as to share unique instances, using the method String#intern().
This ...
correct way to define class variables in Python [duplicate]
... being init always executed after the object is created, it becomes practically equal to define variables outside of init, right?
– jeanc
Jan 29 '12 at 21:33
2
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how to use javascript Object.defineProperty
...rs = new Product("Sneakers",20);
sneakers.discount = 50; // 50, setter is called
sneakers.discount+= 20; // 70, setter is called
sneakers.discount+= 20; // 80, not 90!
alert(sneakers.discount); // getter is called
Note the last but one line: the responsibility for correct discount value was moved ...
How to identify numpy types in python?
...o test for that. And so on. The point is, you have to know what you're actually asking for when you want to do something as unusual as loose manual type switching, but once you know, it's easy to implement.
– abarnert
Mar 11 '16 at 20:41
...
ActiveRecord: List columns in table from console
...del name:
> User
gives:
User(id: integer, name: string, email: string, etc...)
In rails four, you need to establish a connection first:
irb(main):001:0> User
=> User (call 'User.connection' to establish a connection)
irb(main):002:0> User.connection; nil #call nil to stop repl spitti...