Delete last N characters from field in a T-SQL Server database

sql-server

Solution

UPDATE mytable SET column=LEFT(column, LEN(column)-5)

Removes the last 5 characters from the column (every row in mytable)

Problem

I have table of over 4 million rows and accidentally in one column there is more data than needed. For example instead of `ABC` there is `ABC DEFG`. How can I remove that N symbols using TSQL? Please note that I want to delete this characters from database, NOT just select substring. Thank you

Original source