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B-Tree vs Hash Table
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117
You can only access elements by their primary key in a hashtable.
This is faster than with a t...
Stopping python using ctrl+c
... it just hides it to the background and suspends it. You can type fg to recall it.
– Shady Xu
Mar 21 '14 at 3:20
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Read-only and non-computed variable properties in Swift
...g in Objective-C. I have readonly properties, and they cannot be individually changed. However, using a specific method, the properties are changed in a logical way.
...
MongoDB Many-to-Many Association
... user document:
{name:"Joe"
,roles:["Admin","User","Engineer"]
}
To get all the Engineers, use:
db.things.find( { roles : "Engineer" } );
If you want to maintain the roles in separate documents then you can include the document's _id in the roles array instead of the name:
{name:"Joe"
,roles:...
Capture characters from standard input without waiting for enter to be pressed
...oo much on the terminal used that may be connected with stdin (they are usually line buffered). You can, however use a library for that:
conio available with Windows compilers. Use the _getch() function to give you a character without waiting for the Enter key. I'm not a frequent Windows developer...
MongoDB/NoSQL: Keeping Document Change History
... changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can write all changes from all source tables to a single table (more of...
Are HLists nothing more than a convoluted way of writing tuples?
I am really interested in finding out where the differences are, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
...
What are deferred objects?
...As of jQuery 1.5, the Deferred object provides a way to register multiple callbacks into self-managed callback queues, invoke callback queues as appropriate, and relay the success or failure state of any synchronous or asynchronous function.
Deferred Methods:
deferred.done()
Add handlers to be cal...
Multiple levels of 'collection.defaultdict' in Python
...ng specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created.
– interjay
Oct 11 '13 at 12:53
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How to compile a static library in Linux?
...:
target: prerequisites - the rule head
$@ - means the target
$^ - means all prerequisites
$< - means just the first prerequisite
ar - a Linux tool to create, modify, and extract from archives see the man pages for further information. The options in this case mean:
r - replace files existing...