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Oracle 19c SE2 - Performance Views

user545194Aug 4 2022

Hi,
Oracle Database 19c Standard Edition 2 Release 19.0.0.0.0 - Production Version 19.15.0.0.0
We would like to monitor the performance of our database and need to know which views/tables (i.e. SYS.V_$SYSMETRIC_SUMMARY) can be queried in the SE2 version?

Comments

DrClap
Sure, that will work as long as the type in question has an accessible zero-argument constructor. So yes, in your example you could return a new ArrayList or a new HashSet. Not a new ArrayList<Thing>, though, because generics are a compile-time concept only and mean nothing at run time.

By the way it's more traditional to just pass a Class object directly, instead of a wasted object of that class:
public Class<?> method(Class<?> arg) {    
    Class<?> copy = arg.newInstance();
    return copy;
}
And to call that:
ArrayList result = method(ArrayList.class);
843793
@DrClap: shouldn't your method be:
public Object method(Class<?> arg) {    
    Object copy = arg.newInstance();
    return copy;
}
DrClap
Robert.Bossy wrote:
@DrClap: shouldn't your method be:
public Object method(Class<?> arg) {    
Object copy = arg.newInstance();
return copy;
}
Yes, you're right. Or perhaps something like
public T method(Class<? extends T> arg) {    
    T copy = arg.newInstance();
    return copy;
}
Although I have to say, this method doesn't look as useful to me as it apparently did to the OP.
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Added on Aug 4 2022
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