Comparing Selection, Insertion, and Bubble Sorts for database application Explain and compare selection, insertion and bubble sorts. Assume
that your application (say a data base application) deals with 
large records where comparisons are performed by means of integer keys. 
Assume also that your application requires a stable sorting method,
i.e. a method that does not change the relative ordering of elements 
that are equal. Which of these sorting methods would you choose, 
and why? (Hint: consider sorting based on the following integer keys
19, 14(1), 7, 12, 14(2), 10). 

This is a question I'm studying in class, not sure which is the right one and why.
A "database" that isn't ashamed of calling itself "database" will have hundreds of thousands or millions of records. Any algorithm where the number of operations is quadratic except for special cases is totally unsuitable. So the answer is "none of the above". 

You'd do some serious measuring to decide whether to just create an in-memory index (that means you don't sort anything at all, but you just record #1 = 7 at record 3, #2 = 10 at record 6, ...), or use merge sort or Quicksort. Quicksort only if you have a backup, in case there's a problem during the sort.