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How do you effectively model inheritance in a database?
... the type of the child class (similar to the rowType field in the TPH), so mixing the TPT and TPH somehow.
Say we want to design a database that holds the following shape class diagram:
public class Shape {
int id;
Color color;
Thickness thickness;
//other fields
}
public class Rectangle : Shape...
Show or hide element in React
...act circa 2020
In the onClick callback, call the state hook's setter function to update the state and re-render:
const Search = () => {
const [showResults, setShowResults] = React.useState(false)
const onClick = () => setShowResults(true)
return (
<div>
<inp...
How do I fix the Visual Studio compile error, “mismatch between processor architecture”?
...of sense for C# DLLs, they do work either way. But sure, not your C++/CLI mixed mode DLL, it contains unmanaged code that can only work well when the process runs in 32-bit mode. You can get the build system to generate warnings about that. Which is exactly what you got. Just warnings, it still ...
Is there a cross-domain iframe height auto-resizer that works?
I tried a few solutions but wasn't successful. I'm wondering if there is a solution out there preferably with an easy-to-follow tutorial.
...
What is the difference between == and equals() in Java?
...id if you are talking about "static" or "non-static" members; you can also mix all the above...
Here is an example (you can run it):
public final class MyEqualityTest
{
public static void main( String args[] )
{
String s1 = new String( "Test" );
String s2 = new String( "Tes...
Learning Ant path style
Where can I find resources to learn Ant path style conventions? I've gone to the Ant site itself, but couldn't find any information on path styles.
...
Parsing XML with namespace in Python via 'ElementTree'
...ve the .find(), findall() and iterfind() methods an explicit namespace dictionary. This is not documented very well:
namespaces = {'owl': 'http://www.w3.org/2002/07/owl#'} # add more as needed
root.findall('owl:Class', namespaces)
Prefixes are only looked up in the namespaces parameter you pass ...
How can prepared statements protect from SQL injection attacks?
...r separately.
That's all.
The root of the SQL injection problem is in the mixing of the code and the data.
In fact, our SQL query is a legitimate program.
And we are creating such a program dynamically, adding some data on the fly. Thus, the data may interfere with the program code and even al...
Find size of object instance in bytes in c#
For any arbitrary instance (collections of different objects, compositions, single objects, etc)
15 Answers
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What is meant by Resource Acquisition is Initialization (RAII)?
... with resources, it also makes your code much cleaner as you don't need to mix error handling code with the main functionality.
* Update: "local" may mean a local variable, or a nonstatic member variable of a class. In the latter case the member variable is initialized and destroyed with its owner ...