title: MySQL - how to write stored procedure to insert data in to table from two other tables
body: <p>I have three tables (having 4 columns each) of identical columns. First column is Unique ID which is common in all tables, other three columns in two tables have data (integer) of two months. </p>
  
  <p>I want to insert difference of values present in each columns of two tables against each Unique ID in third table.</p>
  
  <p>Please help me to create a procedure in MySQL. </p>