You should not use the Execute Query statement...as that is suppose to be used with select statements...or other statements that are ought to return record(s) from a given database.
When updating or deleting records, you should use the Execute Update method. for example
affectedRecords= st.executeUpdate("DELETE FROM email WHERE email="+'"'+request.getParameter("email1")+'"');
Once you've executed the above statement, you will get an integer value indicating the number of affected row(s)