mysql查询更新重复的条目

i am stuck in a simple update query. i have a table say tabble1 containing 'name' and 'phone_no' column. Now when i upload csv file containing list of name and contact numbers, i want to update name of duplicate number with previous one. For ex. i have a row containing 'max' '8569589652'. now when i upload same number with another name say 'stela' '8569589652' then stela shuld get updated to max.i am stuck in a simple update query. i have a t