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What's the point of 'const' in the Haskell Prelude?
..., no matter the second, you can do:
listOfNothings :: String -> [Maybe Char]
listOfNothings = (map . const) Nothing
or, more explicitly:
listOfNothing st = map (const Nothing) st
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GROUP BY with MAX(DATE) [duplicate]
... to your group by clause, otherwise you need to rethink your query.
Try:
SELECT t.Train, t.Dest, r.MaxTime
FROM (
SELECT Train, MAX(Time) as MaxTime
FROM TrainTable
GROUP BY Train
) r
INNER JOIN TrainTable t
ON t.Train = r.Train AND t.Time = r.MaxTime
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There is no ListBox.SelectionMode=“None”, is there another way to disable selection in a listbox?
How do I disable selection in a ListBox?
16 Answers
16
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MySQL “NOT IN” query
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To use IN, you must have a set, use this syntax instead:
SELECT * FROM Table1 WHERE Table1.principal NOT IN (SELECT principal FROM table2)
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Fastest check if row exists in PostgreSQL
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Use the EXISTS key word for TRUE / FALSE return:
select exists(select 1 from contact where id=12)
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Qt c++ aggregate 'std::stringstream ss' has incomplete type and cannot be defined
...tr();
}
You can also use some other ways to convert int to string, like
char numstr[21]; // enough to hold all numbers up to 64-bits
sprintf(numstr, "%d", age);
result = name + numstr;
check this!
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How to bind inverse boolean properties in WPF?
... which is easily missed when it (as is often the case) is embedded next to chars that look like it (i.e. one/more "("'s and "l"'s and "I"'s).
– Tom
Jan 18 '18 at 1:54
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How to remove unused C/C++ symbols with GCC and ld?
...shorter names for symbols (can help a bit, likely not too much); use const char x[] where possible; ... this paper, though it talks about dynamic shared objects, can contain suggestions that, if followed, can help to make your final binary output size smaller (if your target is ELF).
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How do I capitalize first letter of first name and last name in C#?
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TextInfo.ToTitleCase() capitalizes the first character in each token of a string.
If there is no need to maintain Acronym Uppercasing, then you should include ToLower().
string s = "JOHN DOE";
s = CultureInfo.CurrentCulture.TextInfo.ToTitleCase(s.ToLower());
// Produce...
MySQL “Group By” and “Order By”
I want to be able to select a bunch of rows from a table of e-mails and group them by the from sender. My query looks like this:
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