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PostgreSQL: How to pass parameters from command line?
I have a somewhat detailed query in a script that uses ? placeholders. I wanted to test this same query directly from the psql command line (outside the script). I want to avoid going in and replacing all the ? with actual values, instead I'd like to pass the arguments after the query.
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Do you use NULL or 0 (zero) for pointers in C++?
In the early days of C++ when it was bolted on top of C, you could not use NULL as it was defined as (void*)0 . You could not assign NULL to any pointer other than void* , which made it kind of useless. Back in those days, it was accepted that you used 0 (zero) for null pointers.
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What is Gradle in Android Studio?
Gradle is a bit confusing to me, and also for any new Android developer. Can anyone explain what Gradle in Android Studio is and what its purpose is? Why is it included in Android Studio?
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What is the performance cost of having a virtual method in a C++ class?
Having at least one virtual method in a C++ class (or any of its parent classes) means that the class will have a virtual table, and every instance will have a virtual pointer.
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map vs. hash_map in C++
I have a question with hash_map and map in C++. I understand that map is in STL, but hash_map is not a standard. What's the difference between the two?
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Read file line by line using ifstream in C++
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First, make an ifstream:
#include <fstream>
std::ifstream infile("thefile.txt");
The two standard methods are:
Assume that every line consists of two numbers and read token by token:
int a, b;
while (infile >> a >> b)
{
// p...
Autoreload of modules in IPython [duplicate]
...to have IPython automatically reload all changed code? Either before each line is executed in the shell or failing that when it is specifically requested to. I'm doing a lot of exploratory programming using IPython and SciPy and it's quite a pain to have to manually reload each module whenever I cha...
Using ViewPagerIndicator library with Android Studio and Gradle
I'm trying to use Jake Wharton's ViewPagerIndicator library , but I'm unable to get it working with my Gradle project in Android Studio.
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How can I programmatically determine if my app is running in the iphone simulator?
As the question states, I would mainly like to know whether or not my code is running in the simulator, but would also be interested in knowing the specific iphone version that is running or being simulated.
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Last non-empty cell in a column
Does anyone know the formula to find the value of the last non-empty cell in a column, in Microsoft Excel?
23 Answers
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