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python-pandas and databases like mysql
...rame from it. SQLAlchemy makes it easier to combine SQL conditions Pythonically if you intend to mix and match things over and over.
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Table
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from...
Split comma-separated strings in a column into separate rows
...solution,
and two additional variants of Jaap's data.table methods.
Overall 8 different methods were benchmarked on 6 different sizes of data frames using the microbenchmark package (see code below).
The sample data given by the OP consists only of 20 rows. To create larger data frames, these 20...
Referring to a file relative to executing script
..., because $0 itself is unreliable.
As an alternative, you could use $BASH_SOURCE instead. Something like this:
source "${BASH_SOURCE%/*}/act.conf.sh"
There are some caveats to this solution, too. Check out the FAQ page to see the trade-offs between different solutions. They seem to recommend cd...
How can you iterate over the elements of an std::tuple?
...rloads for every type the tuple might contain. This works best if you know all the tuple elements will share a common base class or something similar.
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mysql error 1364 Field doesn't have a default values
...e makes MySQL more prone to data quality errors, so removing it is not a really good advice.
– Shadow
May 18 '17 at 8:59
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How to change value of process.env.PORT in node.js?
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VAR_1=value VAR_2=11827 node -> simply use a space to use more than one variable on the same command
– p4bloch
Nov 18 '15 at 21:59
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Is a URL allowed to contain a space?
Is a URI (specifically an HTTP URL) allowed to contain one or more space characters? If a URL must be encoded, is + just a commonly followed convention, or a legitimate alternative?
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Hidden features of Ruby
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From Ruby 1.9 Proc#=== is an alias to Proc#call, which means Proc objects can be used in case statements like so:
def multiple_of(factor)
Proc.new{|product| product.modulo(factor).zero?}
end
case number
when multiple_of(3)
puts "Multiple of 3"
when multiple...
Differences between utf8 and latin1
... at least 5.5 or go for another RDBMS like PostgreSQL. In MySQL 5.5+ it's called utf8mb4.
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Why is \r a newline for Vim?
...This answer helped me the most. Also, for more information, :h :s%, especially the last paragraph. (via :h :s)
– dipnlik
Oct 20 '14 at 12:56
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