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What is the reason not to use select *?
...f that column is removed from the table and the query is executed.
You can more easily scan code where that column is being used.
You should always write queries to bring back the least amount of information.
As others mention if you use ordinal column access you should never use select *
If your SQ...
Iterating over every two elements in a list
...a)
for x, y in pairwise(l):
print "%d + %d = %d" % (x, y, x + y)
Or, more generally:
from itertools import izip
def grouped(iterable, n):
"s -> (s0,s1,s2,...sn-1), (sn,sn+1,sn+2,...s2n-1), (s2n,s2n+1,s2n+2,...s3n-1), ..."
return izip(*[iter(iterable)]*n)
for x, y in grouped(l, 2)...
How can I find the current OS in Python? [duplicate]
...ther unixes, and OS X, while os.name is "posix" for all of them.
For much more detailed information, use the platform module. This has cross-platform functions that will give you information on the machine architecture, OS and OS version, version of Python, etc. Also it has os-specific functions to...
How can I use goto in Javascript?
...onsole.log("Hello, world!");
i++;
if(i < 538) goto start;
You can read more about how goto is implemented, but basically, it does some JavaScript preprocessing that takes advantage of the fact that you can simulate a goto with a labelled while loop. So, when you write the "Hello, world!" program...
What are the relative strengths and weaknesses of Git, Mercurial, and Bazaar? [closed]
...available for all revisions, tree-local revnos (standard revision numbers, more akin to those used by svn or other more conventional SCMs) are used in place of content hashes for identifying revisions. Bazaar has support for "lightweight checkouts", in which history is kept on a remote server instea...
List comprehension: Returning two (or more) items for each item
Is it possible to return 2 (or more) items for each item in a list comprehension?
6 Answers
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How is the default max Java heap size determined?
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What's the best way to develop a sideswipe menu like the one in Facebook's new iOS app?
It appears that side-swipe menus are becoming a more common interface element as more information gets crammed into each iPhone app. Facebook has included it in their latest version and the new Gmail app appears to include it as well . I was wondering if anybody had thoughts on the most efficient...
What is “overhead”?
... to the console just so you can do your "hello world". But please, tell me more about low overhead coding.
– corsiKa
Mar 10 '15 at 16:52
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Preventing Laravel adding multiple records to a pivot table
...during an attempt of saving a doublet.
You should also take a look at the more straightforward answer from Barryvdh just below.
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