formatting a property value in dimension in SQL

I am new to BPC 7.5  sp8 Microsoft version 2008 R2. I would like to format the date from mm/dd/yyyy  to yyyy-mm-dd in a member dimension for all members straight in SQL . I tried it and processed the cubes but the record remains the same when I view it from the front end.In TSQL I can easily update the member dimension field with a single update statement

e.g  from 1/8/1984 to 1984-01-08 00:00:00

Doing this from "Manage Dimension members" from the Application is rather long.This update is for 14232 entries. How is this possible because?

What is the sequence of steps I need to follow in SQL so that the update is complete and the application recognizes it?