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Why is MySQL's default collation latin1_swedish_ci?
What is the reasoning behind setting latin1_swedish_ci as the compiled default when other options seem much more reasonable, like latin1_general_ci or utf8_general_ci ?
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Python: using a recursive algorithm as a generator
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117
def getPermutations(string, prefix=""):
if len(string) == 1:
yield prefix + string...
Regex how to match an optional character
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Use
[A-Z]?
to make the letter optional. {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)
You could improve your regex to
^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-...
How can I sort a dictionary by key?
What would be a nice way to go from {2:3, 1:89, 4:5, 3:0} to {1:89, 2:3, 3:0, 4:5} ?
I checked some posts but they all use the "sorted" operator that returns tuples.
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R data formats: RData, Rda, Rds etc
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196
Rda is just a short name for RData. You can just save(), load(), attach(), etc. just like you ...
How to prevent browser page caching in Rails
...se.headers["Pragma"] = "no-cache"
response.headers["Expires"] = "Mon, 01 Jan 1990 00:00:00 GMT"
end
end
Rails 4 and older versions:
class ApplicationController < ActionController::Base
before_filter :set_cache_headers
private
def set_cache_headers
response.headers["Cache-Con...
Array include any value from another array?
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edited Jan 18 at 6:58
answered Oct 15 '10 at 11:55
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Appending to an existing string
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165
You can use << to append to a string in-place.
s = "foo"
old_id = s.object_id
s <<...
How do I calculate percentiles with python/numpy?
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11 Answers
11
Active
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conditional unique constraint
... constraint like this. The difference is, you'll return false if Status = 1 and Count > 0.
http://msdn.microsoft.com/en-us/library/ms188258.aspx
CREATE TABLE CheckConstraint
(
Id TINYINT,
Name VARCHAR(50),
RecordStatus TINYINT
)
GO
CREATE FUNCTION CheckActiveCount(
@Id INT
) RETURNS I...