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Is it a good idea to index datetime field in mysql?
...lication I will have many rows for example I currently have one table with 4 million records. Most of my queries use datetime clause to select data. Is it a good idea to index datetime fields in mysql database?
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Read input from console in Ruby?
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Marius Butuc
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answered Jul 2 '11 at 10:12
siamesiame
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Hex representation of a color with alpha channel?
... transparent red. RGB channels are 0-255 or 0%-100%, alpha is 0-1.
In CSS 4*, you can specify the alpha channel using the 7th and 8th characters of an 8 digit hex colour, or 4th character of a 4 digit hex colour (see CSS Level 4 spec*)
As of May 2019, >80% of users can be expected to understand...
How to sort a list in Scala by two fields?
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4 Answers
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What is the difference between hg forget and hg remove?
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348
'hg forget' is just shorthand for 'hg remove -Af'. From the 'hg remove' help:
...and -Af c...
Why does Typescript use the keyword “export” to make classes and interfaces public?
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Ondra Žižka
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answered Apr 2 '13 at 10:00
FentonFenton...
git command to show all (lightweight) tags creation dates
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edited Apr 20 '16 at 20:46
ndmeiri
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answered ...
ModelState.AddModelError - How can I add an error that isn't for a property?
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Scott BakerScott Baker
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Simple logical operators in Bash
...mands, but they only influence parsing, not grouping. The program x=2; { x=4; }; echo $x prints 4, whereas x=2; (x=4); echo $x prints 2. (Also braces require spaces around them and a semicolon before closing, whereas parentheses don't. That's just a syntax quirk.)
With a leading dollar sign, ${VAR...
Plotting a list of (x, y) coordinates in python matplotlib
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184
As per this example:
import numpy as np
import matplotlib.pyplot as plt
N = 50
x = np.random.r...