To update the content of the table in Sqlite Database in Android

I have created a database in Sqlite Android Application, there are two fields in the table i.e Name and Email. I want to update the contents of the table, the query that i am using is.

db.update(TABLENAME,cv,"id=?",new String[]{String.valueOf(7)});

As this will update the content that have the ID 7, but i want to update the table by matching the name entered.