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Int division: Why is the result of 1/3 == 0?
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The two operands (1 and 3) are integers, therefore integer arithmetic (division here) is used. Declaring the result variable as double just causes an implicit conversion to occur after division.
Integer division of course returns the tr...
How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
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You are so close! All you need to do is select BOTH the home and its max date time, then join back to the topten table on BOTH fields:
SELECT tt.*
FROM topten tt
INNER JOIN
(SELECT home, MAX(datetime) AS MaxDateTime
FROM topten
GROUP BY home) groupedtt
ON tt.home = groupe...
How do I wait for an asynchronously dispatched block to finish?
I am testing some code that does asynchronous processing using Grand Central Dispatch. The testing code looks like this:
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JavaScript open in a new window, not tab
...,location=0,menubar=0'. You can verify it by omitting this third parameter and leaving '_blank' there as the 2nd parameter.
– user1451111
Aug 25 '17 at 4:49
1
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JavaScript - onClick to get the ID of the clicked button
...l reference exception using JQuery's event.target.id (for me, both Firefox and IE were throwing it), this is a great solution that works in all three major browsers.
– X3074861X
Aug 8 '13 at 16:30
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Are booleans as method arguments unacceptable? [closed]
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Although in this case I'd maybe rather have turnLightOn() and turnLightOff(), depending on the situation.
– skaffman
Sep 25 '08 at 20:50
14
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Example: Communication between Activity and Service using Messaging
I couldn't find any examples of how to send messages between an activity and a service, and I have spent far too many hours figuring this out. Here is an example project for others to reference.
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Group by month and year in MySQL
...Performance... my test of GROUP BY YEAR(date), MONTH(date) DESC; (~450 ms) and GROUP BY DATE_FORMAT(date,'%Y-%m') (~850 ms) on a InnoDB table with > 300,000 entries showed the former (the marked answer to this question) took ~half the time as the latter.
– ow3n
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How to use OpenSSL to encrypt/decrypt files?
I want to crypt and decrypt one file using one password.
10 Answers
10
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How can I check if a scrollbar is visible?
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Note that on Macs the scrollbar floats over the content and disappears when not in use. On Windows it is always visible and takes up horizontal space. Therefor, just because content can be scrolled (which this function detects) does not mean that a scrollbar is necessarily present...