Joined: 31 Oct 2006 Posts: 971 Location: Richmond, Virginia
Well, let's think about it.
Your first proposed solution would re-sort a large number of records that had been sorted, except that you strung them together via concatenate, thereby totally unsorting the whole shebang (I'm not sure of the origin of this technical term).
Your 2nd solution takes already sorted files and then just interleaves them, each loop taking the lowest ranking top record from one of the ten files.
Yes, but a pretty well known one. Sorting is more complex than merging and generally requires the use of more resources. For example, a SORT may require the use of intermediate storage (e.g. hiperspace or work space) whereas a MERGE never does.