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Postgres and Indexes on Foreign Keys and Primary Keys
...omatically put indexes on Foreign Keys and Primary Keys? How can I tell? Is there a command that will return all indexes on a table?
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What are the dark corners of Vim your mom never told you about? [closed]
...ee %
I often forget to sudo before editing a file I don't have write permissions on. When I come to save that file and get a permission error, I just issue that vim command in order to save the file without the need to save it to a temp file and then copy it back again.
You obviously have to be o...
Using only CSS, show div on hover over
... when someone hovers over an <a> element, but I would like to do this in CSS and not JavaScript. Do you know how this can be achieved?
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What is the relationship between the docker host OS and the container base image OS?
... I can install a Fedora container or a different version of ubuntu? (there is an example where the user installed busybox in the container.)
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Using the HTML5 “required” attribute for a group of checkboxes?
...a form field has the attribute required='required' ;
and the form field is empty/blank;
and the submit button is clicked;
the browsers detects that the "required" field is empty and does not submit the form; instead browser shows a hint asking the user to type text into the field.
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Pad a number with leading zeros in JavaScript [duplicate]
...in() doesn't, or at least not completely; it treats them as if their value is the empty string. Thus you get a copy of the zero character (or whatever "z" is) between each of the array elements; that's why there's a + 1 in there.
Example usage:
pad(10, 4); // 0010
pad(9, 4); // 0009
pad...
Is there a MySQL option/feature to track history of changes to records?
...ords in a MySQL database. So when a field has been changed, the old vs new is available and the date this took place. Is there a feature or common technique to do this?
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find -exec cmd {} + vs | xargs
Which one is more efficient over a very large set of files and should be used?
3 Answers
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In Python, using argparse, allow only positive integers
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This should be possible utilizing type. You'll still need to define an actual method that decides this for you:
def check_positive(value):
ivalue = int(value)
if ivalue <= 0:
raise argparse.ArgumentTypeError...
How to initialize all members of an array to the same value?
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Unless that value is 0 (in which case you can omit some part of the initializer
and the corresponding elements will be initialized to 0), there's no easy way.
Don't overlook the obvious solution, though:
int myArray[10] = { 5, 5, 5, 5, 5, 5,...