"Praveen Raja" <praveen(dot)raja(at)netlight(dot)se> writes:
> I know that having indexes on the table adds an overhead but again does
> this overhead increase (for an INSERT operation) with the number of rows
> the table contains?
Typical index implementations (such as b-tree) have roughly O(log N)
cost to insert or lookup a key in an N-entry index. So yes, it grows,
though slowly.
regards, tom lane