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PreparedStatement IN clause alternatives?
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195
An analysis of the various options available, and the pros and cons of each is available here....
How can I pass a list as a command-line argument with argparse?
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10 Answers
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 ...
How are multi-dimensional arrays formatted in memory?
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147
A static two-dimensional array looks like an array of arrays - it's just laid out contiguously...
How to control the line spacing in UILabel
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edited Jan 5 '18 at 8:31
Bart van Kuik
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answered Ap...
How to read a file without newlines?
...ead().splitlines()
Or you can strip the newline by hand:
temp = [line[:-1] for line in file]
Note: this last solution only works if the file ends with a newline, otherwise the last line will lose a character.
This assumption is true in most cases (especially for files created by text editors, ...
Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql st
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21 Answers
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What is the minimum I have to do to create an RPM file?
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178
I often do binary rpm per packaging proprietary apps - also moster as websphere - on linux.
So...
How to get next/previous record in MySQL?
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edited Jul 10 '12 at 10:53
Vimalnath
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arrayfun can be significantly slower than an explicit loop in matlab. Why?
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101
You can get the idea by running other versions of your code. Consider explicitly writing out t...