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How can I list all collections in the MongoDB shell?
... Can we please get db.listCollections() as the answer shown here and checked in green? Otherwise people are making the same mistake I did countless times when they come to this answer - and attempt to use db.getCollectionNames and the error comes back db.collectionNames is not a function....
Java int to String - Integer.toString(i) vs new Integer(i).toString()
...t is to print an int, you'd use the first one because it's lighter, faster and doesn't use extra memory (aside from the returned string).
If you want an object representing an integer value—to put it inside a collection for example—you'd use the second one, since it gives you a full-fledged o...
What are the primary differences between Haskell and F#? [closed]
I've searched on the Internet for comparisons between F# and Haskell but haven't found anything really definitive. What are the primary differences and why would I want to choose one over the other?
...
Stripping everything but alphanumeric chars from a string in Python
...intable (part of the built-in string module). The use of compiled '[\W_]+' and pattern.sub('', str) was found to be fastest.
$ python -m timeit -s \
"import string" \
"''.join(ch for ch in string.printable if ch.isalnum())"
10000 loops, best of 3: 57.6 usec per loop
$ python -m timeit -...
SQL Server: SELECT only the rows with MAX(DATE)
...o join on a query, as per Cularis' answer.
Alternatively, the most simple and straight forward way is a correlated-sub-query in the WHERE clause.
SELECT
*
FROM
yourTable AS [data]
WHERE
DateEntered = (SELECT MAX(DateEntered) FROM yourTable WHERE orderNo = [data].orderNo)
Or...
WHERE
ID ...
What is an idempotent operation?
...g that x in the mathematical definition represents the state of an object, and f is an operation that may mutate that object. For example, consider the Python set and its discard method. The discard method removes an element from a set, and does nothing if the element does not exist. So:
my_set.dis...
How do I copy an object in Java?
... to copy the object, but don't use it. It's way too easy to create a class and do improper clone method. If you are going to do that, read at least what Joshua Bloch has to say about it in Effective Java.
share
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What is the easiest way to make a C++ program crash?
...program that interfaces with a different crashy process (that's out of my hands). Unfortunately the program I'm interfacing with doesn't even crash reliably! So I want to make a quick C++ program that crashes on purpose but I don't actually know the best and shortest way to do that, does anyone know...
Make XAMPP/Apache serve file outside of htdocs [closed]
...
Ok, per pix0r's, Sparks' and Dave's answers it looks like there are three ways to do this:
Virtual Hosts
Open C:\xampp\apache\conf\extra\httpd-vhosts.conf.
Un-comment ~line 19 (NameVirtualHost *:80).
Add your virtual host (~line 36):
<Virtua...
How to import JsonConvert in C# application?
...
right click on the project and select Manage NuGet Packages..
In that select Json.NET and install
After installation,
use the following namespace
using Newtonsoft.Json;
then use the following to deserialize
JsonConvert.DeserializeObject
...