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Changing the maximum length of a varchar column?
...
You need
ALTER TABLE YourTable ALTER COLUMN YourColumn <<new_datatype>> [NULL | NOT NULL]
But remember to specify NOT NULL explicitly if desired.
ALTER TABLE YourTable ALTER COLUMN YourColumn VARCHAR (500) NOT NULL;
If you leave it unspecified as below...
ALTER TABLE Your...
Get the date (a day before current time) in Bash
... a one-liner, so cut and paste should work -- no line endings assumed. date_days_past () { days_past=${1:-0}; if ! date -v-${days_past}d +%Y%m%d 2>/dev/null; then date --date="-${days_past} day" +%Y%m%d; fi }
– Noah Spurrier
May 16 '16 at 21:29
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How do you check in python whether a string contains only numbers?
...mbers. Formally, a digit is a character that has the property value Numeric_Type=Digit or Numeric_Type=Decimal.
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Deleting DataFrame row in Pandas based on column value
...If I'm understanding correctly, it should be as simple as:
df = df[df.line_race != 0]
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Difference between Math.Floor() and Math.Truncate()
...ound cha cha, real smooth... (go to closest side)
Let's go to work! (⌐□_□)
To the left... Math.floor
Take it back now y'all... --
Two hops this time... -=2
Everybody clap your hands ✋✋
How low can you go? Can you go down low? All the way to the floor?
if (this == "wrong")
return "i don...
Histogram Matplotlib
... compute the widths using np.diff, pass the widths to ax.bar and use ax.set_xticks to label the bin edges:
import matplotlib.pyplot as plt
import numpy as np
mu, sigma = 100, 15
x = mu + sigma * np.random.randn(10000)
bins = [0, 40, 60, 75, 90, 110, 125, 140, 160, 200]
hist, bins = np.histogram(x,...
Should operator
...lic:
explicit Paragraph(std::string const& init)
:m_para(init)
{}
std::string const& to_str() const
{
return m_para;
}
bool operator==(Paragraph const& rhs) const
{
return m_para == rhs.m_para;...
What is the maven-shade-plugin used for, and why would you want to relocate Java packages?
...e you will need only one big JAR instead of tons of small JARs to run your app. It also ease distribution in some case.
Just a side-note. Avoid using uber-jar as Maven dependency, as it is ruining the dependency resolution feature of Maven. Normally we create uber-jar only for the final artifact...
Ruby on Rails: How can I revert a migration with rake db:migrate?
...to revert.
eg. if you want to revert a migration with file name 3846656238_create_users.rb
rake db:migrate:down VERSION=3846656238
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Best way to change the background color for an NSView
...:dirtyRect];
}
In Swift:
class MyView: NSView {
override func draw(_ dirtyRect: NSRect) {
super.draw(dirtyRect)
// #1d161d
NSColor(red: 0x1d/255, green: 0x16/255, blue: 0x1d/255, alpha: 1).setFill()
dirtyRect.fill()
}
}
...
