Any column that is not modified retains its original values, except in certain queries using the CASE expression. See CASE expression for a description of CASE expressions. To add, drop, or modify a ...

9 best practices for faster SQL queries Retrieve only the columns you need Use CASE instead of UPDATE for conditional column updates Keep large-table queries to a minimum Pre-stage your data ...

Click New Query in the context menu. In the Query window, type a statement such as the following: SELECT client_id, first_name, last_name INTO new_table FROM old_table; GO ...