Hi Friends,

Am new to this forum, hoping to get some urgent help from THE EXPERTS
Pls read heading as - Need to delete duplicate of a column C based on column B and keep Column B if unique value(occurs more than once) to based on columnA
And expand the current selection(i mean delete that row if deleting the value of the cell)

Working on a spreadsheet which contains million record, 50 columns.
Which 1) I have sorted Column B Low to high, and Column C Latest to Oldest
Now i want to keep the latest time stamp(even if its repetitive N number of times, i would like to keep it like even once or even N times). But delete rest of the dates for that particular duplicated Column B value and expand the current selection.

I hope i could get some help. Many Thanks.

Illustrated an EXAMPLE

A B C
1 1111 12 Aug 2017 19:45:43:20
2 1111 12 Aug 2017 19:45:43:20
3 1111 12 Aug 2017 19:45:43:20
4 1111 12 Aug 2017 09:45:48:20
5 1111 12 Aug 2017 09:45:48:20
6 2222 17 Aug 2017 21:25:43:20
7 2222 17 Aug 2017 21:25:43:20
8 2222 11 Aug 2017 21:25:43:22
9 3333 20 Aug 2017 19:45:43:20
10 3333 20 Aug 2017 19:45:43:20
11 3333 20 Aug 2017 19:45:43:20
12 3333 20 Aug 2017 19:45:43:20
13 3333 20 Aug 2017 19:45:43:20
14 4444 25 Aug 2017 19:45:43:20
15 4444 21 Aug 2017 19:45:43:20


From above i want to keep 1,2,3,6,7,9,10,11,12,13,14
and delete 4,5,8,15 and also expand the current selection