On 7/2/13 3:22 PM, Dan Kimmel wrote:
There's an implied index on the primary key of a file. So the
database engine didn't touch the file at all, it just read straight
from the index.


Opening a result set doesn't fetch all the rows, just the first
handful. The rest are fetched as you "next()" through the result set.
So you'd probably get the same response whether the table had
half-a-million rows or thirty or thirty million.

Actually, I instructed Squirrel to fetch and display the entire result set. But the point is that I could use that long, narrow result set of just the index to find the start point for a short, broad result set, when scrolling backwards through the file, and I could reasonably search the long, narrow result set to find the ordinal starting position when repositioning by key.

My head hurts after writing that last sentence.


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