working with HUGE spreadsheet

Question

i have about 300,000 records in this spreadsheet. and there are a couple hundred columns!!

one of the columns is the social security number and i need to replace it with some random identifier. i cant really do a vlookup because that is too taxing so i think i am going to write a macro

can anyone please suggest to me how do i do this?

please note that the social security numbers appear multiplle times. so i need them to map correctly to the new unique identifier

Answer 1

Why not simply enter a Random number in the column in question, like =RAND(), double-click the bottom corner of the cell to copy the formula to the bottom of your sheet, then copy/paste special value the column on itself to get rid of the formula?

Answer 2

Create a hash based on the current SSN.

An example is here using SHA1 hash. Plenty of other options exist, including creating your own.