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Add unique constraint to combination of two columns
I have a table and, somehow, the same person got into my Person table twice. Right now, the primary key is just an autonumber but there are two other fields that exist that I want to force to be unique.
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What is the best method of handling currency/money?
...on.
If you insist on using integers, you will have to manually convert to and from BigDecimals everywhere, which will probably just become a pain.
As pointed out by mcl, to print the price, use:
number_to_currency(price, :unit => "€")
#=> €1,234.01
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How do I pre-populate a jQuery Datepicker textbox with today's date?
...Update: There are reports this no longer works in Chrome.
This is concise and does the job (obsolete):
$(".date-pick").datepicker('setDate', new Date());
This is less concise, utilizing chaining allows it to work in chrome (2019-06-04):
$(".date-pick").datepicker().datepicker('setDate', new Dat...
How do I (or can I) SELECT DISTINCT on multiple columns?
...on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
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What it the significance of the Javascript constructor property?
Trying to bend by head around Javascript's take on OO...and, like many others, running into confusion about the constructor property. In particular, the significance of the constructor property, as I can't seem to make it have any effect. E.g.:
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Elegant Python function to convert CamelCase to snake_case?
...', name).lower()
print(name) # camel_case_name
If you do this many times and the above is slow, compile the regex beforehand:
pattern = re.compile(r'(?<!^)(?=[A-Z])')
name = pattern.sub('_', name).lower()
To handle more advanced cases specially (this is not reversible anymore):
def camel_to_sn...
How is the AND/OR operator represented as in Regular Expressions?
...ou want to build a the regex dynamically to contain other words than part1 and part2, and that you want order not to matter. If so you can use something like this:
((^|, )(part1|part2|part3))+$
Positive matches:
part1
part2, part1
part1, part2, part3
Negative matches:
part1, //with ...
How to delete the contents of a folder?
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If you're working with a very large directory, and particularly a network directory on windows, and you can control the environment in which this program runs, it might be worth using Py3.5's "os.scandir(folder)" function instead of listdir. The syntax is quite different ...
What's the difference between ngModel.$modelValue and ngModel.$viewValue
...tion, but it might just be that you're a little confused. The $modelValue and $viewValue have one distinct difference. It is this:
As you already noted above:
$viewValue: Actual string (or Object) value in the view.
$modelValue: The value in the model, that the control is bound to.
I'm go...
How to set DialogFragment's width and height?
...gment in an xml layout file (let's call it layout_mydialogfragment.xml ), and its layout_width and layout_height attributes particularly (to be 100dp each let's say). I then inflate this layout in my DialogFragment's onCreateView(...) method as follows:
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