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What is the difference between UNION and UNION ALL?
...
UNION removes duplicates, whereas UNION ALL does not.
In order to remove duplicates the result set must be sorted, and this may have an impact on the performance of the UNION, depending on the volume of data being sorted, and the settings of various RDBMS parameters ( For Oracle PG...
How to quickly open a file in Visual Studio 2012
...tches to previously opened file
Ctrl + Shift + -: Does the same in reverse order
Ctrl + Tab: Again switches to previous file
Ctrl + Shift + Tab: Does the same in reverse order
Hold Ctrl and press Tab multiple times: Switches to selected file
Hold Ctrl, press Tab and release Tab, then select fi...
Merging between forks in GitHub
...ll is nothing more than a macro that does git fetch and git merge, in that order. You just need to fetch the list of commits from the first person's repository and then merge their branch into your tree. Merging should do the right thing with your commits on both branches.
GitHub, in all its perpet...
What is the difference between return and return()?
...allowed because they are allowed in any expression to influence evaluation order, but in your examples they're just superfluous.
return is not a function, but a statement. It is syntactically similar to other simple control flow statements like break and continue that don't use parentheses either.
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Which HTML elements can receive focus?
...ml5/… Basically, a value of 0 makes the element focusable but leaves its ordering up to the browser.
– natevw
Mar 31 '14 at 22:58
7
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MySQL SELECT only not null values
...SELECT DISTINCT (
SELECT title
FROM test
WHERE title IS NOT NULL
ORDER BY id DESC
LIMIT 1
) title, (
SELECT body
FROM test
WHERE body IS NOT NULL
ORDER BY id DESC
LIMIT 1
) body
FROM test
I hope help you.
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Using -performSelector: vs. just calling the method
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- (void)performSelector:(SEL)aSelector target:(id)target argument:(id)arg order:(NSUInteger)order modes:(NSArray *)modes;
- (void)performSelectorOnMainThread:(SEL)aSelector withObject:(id)arg waitUntilDone:(BOOL)wait modes:(NSArray *)array;
- (void)performSelectorOnMainThread:(SEL)aSelector withObj...
Is there a CSS selector for elements containing certain text?
...s it working just 'cos male is first? Bug waiting to happen if they are re-ordered?
– Michael Durrant
Mar 26 '16 at 22:56
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How to select rows that have current day's timestamp?
...t
WHERE DATE(timestamp) = CURDATE() --- using DATE(timestamp)
ORDER BY timestamp ;
Explain:
ID SELECT_TYPE TABLE TYPE POSSIBLE_KEYS KEY KEY_LEN REF
1 SIMPLE test ALL
ROWS FILTERED EXTRA
6671 100 Using where; Using filesort
It filters all (6671) rows and ...
Swing vs JavaFx for desktop applications [closed]
...and, if you want to do transitions / animations / video stuff then this is orders of magnitude easier in FX.
One other thing to bear in mind is (perhaps) look and feel. If you absolutely must have the default system look and feel, then JavaFX (at present) can't provide this. Not a big must have for...