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How to randomly select rows in SQL?
... 2005. In my db, I have a table "customerNames" which has two columns "Id" and "Name" and approx. 1,000 results.
11 Answer...
Calculate the number of business days between two dates?
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I've had such a task before and I've got the solution.
I would avoid enumerating all days in between when it's avoidable, which is the case here. I don't even mention creating a bunch of DateTime instances, as I saw in one of the answers above. This is ...
Text Progress Bar in the Console [closed]
I wrote a simple console app to upload and download files from an FTP server using the ftplib.
31 Answers
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How to insert a SQLite record with a datetime set to 'now' in Android application?
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so above you are taking a Date object and converting it to a string to be placed in a sqlite column.. but when you pull that string from the database, how do you convert it back to a Date object?
– erik
Apr 30 '15 at 3:34
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Cannot use ref or out parameter in lambda expressions
...ld need to be visible on the ref parameter itself. Both within the method and in the caller.
These are somewhat incompatible properties and are one of the reasons they are disallowed in lambda expressions.
share
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“int main (vooid)”? How does that work?
I recently had to type in a small C test program and, in the process, I made a spelling mistake in the main function by accidentally using vooid instead of void .
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How do I explicitly instantiate a template function?
...T] There seems to be (a lot) of confusion regarding explicit instantiation and specialization.
The code I posted above deals with explicit instantiation. The syntax for specialization is different.
Here is syntax for specialization:
template <typename T> void func(T param) {} // definition
t...
Catch Ctrl-C in C
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With a signal handler.
Here is a simple example flipping a bool used in main():
#include <signal.h>
static volatile int keepRunning = 1;
void intHandler(int dummy) {
keepRunning = 0;
}
// ...
int main(void) {
signal(SIG...
What does “O(1) access time” mean?
...een this term "O(1) access time" used to mean "quickly" but I don't understand what it means. The other term that I see with it in the same context is "O(n) access time". Could someone please explain in a simple way what these terms mean?
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Explain the use of a bit vector for determining if all characters are unique
...ay be a little bit faster, because operations with bits are very low level and can be executed as-is by CPU. BitVector allows writing a little bit less cryptic code instead plus it can store more flags.
For future reference: bit vector is also known as bitSet or bitArray. Here are some links to thi...