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What is the difference between Non-Repeatable Read and Phantom Read?
...solation level to be used?
What isolation level you need depends on your application. There is a high cost to a "better" isolation level (such as reduced concurrency).
In your example, you won't have a phantom read, because you select only from a single row (identified by primary key). You can ha...
Why use Ruby instead of Smalltalk? [closed]
...to facilitate integration. Smalltalk never really gained a body of hybrid application support in the way that Python and Ruby have, so the concept of 'smalltalk as embedded scripting language' never caught on.As an aside, Java was not the easiest thing to interface with other code bases (JNI is fai...
Multiprocessing vs Threading Python [duplicate]
...t properly release the GIL will run in parallel
Great option for I/O-bound applications
Cons
cPython - subject to the GIL
Not interruptible/killable
If not following a command queue/message pump model (using the Queue module), then manual use of synchronization primitives become a necessity (dec...
Create request with POST, which response codes 200 or 201 and content
...2:40 GMT
Location: http://stackoverflow.com/a/36373586/12597
Content-Type: application/xml
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<questionID>1860645</questionID>
<answerID>36373586</answerID>
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How to “perfectly” override a dict?
...inimal version that shuts the ABC up.
from collections.abc import MutableMapping
class TransformedDict(MutableMapping):
"""A dictionary that applies an arbitrary key-altering
function before accessing the keys"""
def __init__(self, *args, **kwargs):
self.store = dict()
...
What is Bootstrap?
...ated by Twitter) that you can use as a basis for creating web sites or web applications.
More information and links to download
Getting started
Examples
Themes
Bootply - Bootstrap Editor and Builder
Update
The official bootstrap website is updated and includes a clear definition.
"Bootstrap i...
Optimistic vs. Pessimistic locking
...abort the transaction and the user can re-start it.
This strategy is most applicable to high-volume systems and three-tier architectures where you do not necessarily maintain a connection to the database for your session. In this situation the client cannot actually maintain database locks as the ...
CORS - What is the motivation behind introducing preflight requests?
...ght requests have nothing to do with security, and they have no bearing on applications that are being developed now, with an awareness of CORS. Rather, the preflight mechanism benefits servers that were developed without an awareness of CORS, and it functions as a sanity check between the client an...
For-each over an array in JavaScript
... it handy).
Unless you're supporting obsolete browsers like IE8 (which NetApps shows at just over 4% market share as of this writing in September 2016), you can happily use forEach in a general-purpose web page without a shim. If you do need to support obsolete browsers, shimming/polyfilling forEa...
What would be C++ limitations compared C language? [closed]
...u are working in. (In some cases this is possible with a few extern "C" wrapper functions, depending on how template/inline a C++ library is.)
Taking the first C file in a project I'm working on, this is what happens if you just swap gcc std=c99 for g++:
sandiego:$ g++ -g -O1 -pedantic -mfpmath=...