Is there a way to go through a database and just delete/update to null the records of a particular value

So for example if you had the values

director            producer            writer              leadrole
bob holness     bob holness        bob holness
wayne smith    wayne smith                            bob holness

And you want to delete any entry of bob holness from the database, but without deleting the whole record, so for example wayne smith would remain.
Is this possible?

You could carry out a search and replace routine as I have created on my blog:

This link is for a routine to search for a particular text in all database columns that hold text:
http://amitchandnz.wordpress.com/2009/02/26/search-text-in-all-tables/

This link is for a routine to search and replace text in all database columns that hold text:
http://amitchandnz.wordpress.com/2009/02/10/search-replace-database-column-text/

Thanks for the link

but when I try creating the procedure http://amitchandnz.wordpress.com/2009/02/10/search-replace-database-column-text/

I get the message #1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '@iSearchString VARCHAR(100)
                ,@iReplaceString VARCHAR(100)

I am using MySQL client version: 4.1.22

 Ah sorry about that, I wrote those scripts for SQL Server 2005 as that is what I work on.

I am using the syntax: REPLACE(str,from_str,to_str)

to replace data in my table. However I have a slight issue I would like to address, when I have the following records

jon  | jonathon | jonas | jonny

and I do the replace with

REPLACE(names, jon, '')

I am left with 

     | athon | as | ny

Is there a way that it can only replaces 'whole words' and not replace the string where it is part of a larger string?