mySQL UPDATE query returns “0 rows affected”

Question

I have this query:

UPDATE phonecalls 
   SET Called = \"Yes\" 
 WHERE PhoneNumber = \"999 29-4655\"

My table is phonecalls, I

Answer 1

1. Does it say Rows matched: 1 Changed: 0 Warnings: 0? Then maybe it's already set to that value.
2. Did you try single quotes vs. double quotes?
3. "999 29-4655" is the space a space or a tab and is it consistent in your query and the database?