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Select rows which are not present in other table
...task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgres
FROM ip_location
WHERE ip = l.ip
);
Also consider:
What is easier to read in EXISTS...
SQL query to select dates between two dates
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you should put those two dates between single quotes like..
select Date, TotalAllowance from Calculation where EmployeeId = 1
and Date between '2011/02/25' and '2011/02/27'
or can use
select Date, TotalAllowance from Calculation where EmployeeId = 1
and Da...
Get the index of the nth occurrence of a string?
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Note: I have added Regex.Escape to original solution to allow searching characters which have special meaning to regex engine.
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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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How do I (or can I) SELECT DISTINCT on multiple columns?
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SELECT DISTINCT a,b,c FROM t
is roughly equivalent to:
SELECT a,b,c FROM t GROUP BY a,b,c
It's a good idea to get used to the GROUP BY syntax, as it's more powerful.
For your query, I'd do it like this:
UPDATE sale...
jQuery get value of selected radio button
The problem statement is simple. I need to see if user has selected a radio button from a radio group. Every radio button in the group share same id.
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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 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 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 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...