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IN vs OR in the SQL WHERE Clause
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I think oracle is smart enough to convert the less efficient one (whichever that is) into the other. So I think the answer should rather depend on the readability of each (where I think that IN clearly wins)
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Why isn't SQL ANSI-92 standard better adopted over ANSI-89?
...WHERE clause.
For my part, I do all my joins in the SQL-92 syntax, and I convert code where I can. It's the cleaner, more readable and powerful way to do it. But it's hard to convince someone to use the new style, when they think it hurts them in terms of more typing work while not changing the qu...
I've found my software as cracked download on Internet, what to do?
...ering renting your software for $0.99/day to grab some impulse buyers, and convert them into full customers by offering them the $0.99/day back as a discount when they buy the full version.
– MSalters
Aug 24 '10 at 14:22
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.NET NewtonSoft JSON deserialize map to a different property name
...re to have the response [deserilized object] have value for EightyMinScore and not eighty_min_score
– Gaurravs
Jan 10 '19 at 11:17
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Accessing dict keys like an attribute?
...he rules of the language :) And I wouldn't want AttrDict to automagically convert space-containing fields into something different.
– Yurik
Feb 11 '19 at 18:37
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Is it faster to count down than it is to count up?
... technique.
Also, a good optimizing compiler these days should be able to convert your count up loop source code into count down to zero machine code (depending on how you use the loop index variable) so there really isn't any reason to write your loops in strange ways just to squeeze a cycle or tw...
Why are these constructs using pre and post-increment undefined behavior?
... can't predict the behavior when the code is run.
As far as I know, the standard doesn't explicitly say why the concept of undefined behavior exists. In my mind, it's simply because the language designers wanted there to be some leeway in the semantics, instead of i.e. requiring that all implementa...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable icc , will eliminate the library call for pow(a,6) .)
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Select by partial string from a pandas DataFrame
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Is it possible to convert .str.contains to use .query() api?
– zyxue
Mar 1 '17 at 17:25
3
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Output array to CSV in Ruby
...{ |csv, row| csv << CSV.generate_line(row) }.join(""))}
NOTE:
To convert an active record database to csv would be something like this I think
CSV.open(fn, 'w') do |csv|
csv << Model.column_names
Model.where(query).each do |m|
csv << m.attributes.values
end
end
H...