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Get names of all keys in the collection
I'd like to get the names of all the keys in a MongoDB collection.
21 Answers
21
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SQL Add foreign key to existing column
...sed an error trying to create the relationships to the other table. Thanks all.
– ExceptionLimeCat
Apr 30 '12 at 20:35
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Is there a way to detach matplotlib plots so that the computation can continue?
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Use matplotlib's calls that won't block:
Using draw():
from matplotlib.pyplot import plot, draw, show
plot([1,2,3])
draw()
print('continue computation')
# at the end call show to ensure window won't close.
show()
Using interactive mode:
from...
List of foreign keys and the tables they reference
...key is described in the columns r_owner and r_constraint_name of the table ALL_CONSTRAINTS. This will give you the info you want:
SELECT a.table_name, a.column_name, a.constraint_name, c.owner,
-- referenced pk
c.r_owner, c_pk.table_name r_table_name, c_pk.constraint_name r_pk
FROM...
Allowed characters in Linux environment variable names
What characters are allowed in Linux environment variable names? My cursory search of man pages and the web did only produce information about how to work with variables, but not which names are allowed.
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Random String Generator Returning Same String [duplicate]
...om instance in the method, which causes it to return the same values when called in quick succession. I would do something like this:
private static Random random = new Random((int)DateTime.Now.Ticks);//thanks to McAden
private string RandomString(int size)
{
StringBuilder builder = new...
Using Django time/date widgets in custom form
...e many hacks required, probably ought to caution you against doing this at all. It's relying on undocumented internal implementation details of the admin, is likely to break again in future versions of Django, and is no easier to implement than just finding another JS calendar widget and using that....
How do I find the duplicates in a list and create another list with them?
... @Hugo, to see the list of duplicates, we just need to create a new list called dup and add an else statement. For example: dup = [] else: dup.append(x)
– Chris Nielsen
Apr 29 '16 at 16:45
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Looking to understand the iOS UIViewController lifecycle
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All these commands are called automatically at the appropriate times by iOS when you load/present/hide the view controller. It's important to note that these methods are attached to UIViewController and not to UIViews themsel...
How can I setup & run PhantomJS on Ubuntu?
... to add one additional symlink to /usr/bin/, and I did direct symlinks for all 3 - see below.
I'm installing on Ubuntu server Natty Narwhal.
This is exactly what I did.
cd /usr/local/share
sudo wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo tar xjf ...