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MySQL/SQL: Group by date only on a Datetime column
...GROUP BY DATE(a_table.mydate);
Or you can GROUP BY the alias as @orlandu63 suggested:
SELECT SUM(foo), DATE(mydate) DateOnly FROM a_table GROUP BY DateOnly;
Though I don't think it'll make any difference to performance, it is a little clearer.
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What's the difference between Unicode and UTF-8? [duplicate]
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edited Oct 12 '12 at 23:38
hannson
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Run an OLS regression with Pandas Data Frame
... statsmodels.formula.api as sm
>>> df = pd.DataFrame({"A": [10,20,30,40,50], "B": [20, 30, 10, 40, 50], "C": [32, 234, 23, 23, 42523]})
>>> result = sm.ols(formula="A ~ B + C", data=df).fit()
>>> print(result.params)
Intercept 14.952480
B 0.401182
C ...
In what order are Panels the most efficient in terms of render time and performance?
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3 Answers
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Why does make think the target is up to date?
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edited May 30 '12 at 6:43
answered Oct 14 '10 at 9:30
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The server committed a protocol violation. Section=ResponseStatusLine ERROR
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Darin DimitrovDarin Dimitrov
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Open Sublime Text from Terminal in macOS
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I finally got this to work on my OSX box. I used these steps to get it to work:
Test subl fro...
How does the socket API accept() function work?
...ients, 10.0.0.1 and 10.0.0.2.
10.0.0.1 opens a connection on local port 1234 and connects to the server. Now the server has one socket identified as follows:
10.0.0.1:1234 - 192.168.1.1:80
Now 10.0.0.2 opens a connection on local port 5678 and connects to the server. Now the server has two s...
Ruby on Rails: How do I add placeholder text to a f.text_field?
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With rails >= 3.0, you can simply use the placeholder option.
f.text_field :attr, placeholder: "placeholder text"
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What are the correct link options to use std::thread in GCC under linux?
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edited Oct 4 '17 at 23:54
Earth Engine
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