title: Creating a column which should be auto generated by concatenating values in other columns in a table
body: <p>I got a table in a SQL database with four columns: ID, Comp_Id, Cont_Id and Comp_Cont_Id. The values into ID, Comp_Id, Cont_Id columns are entered manually and the value in the column Comp_Cont_Id is to be generated automatically by concatenating the values in ID, Comp_Id, Cont_Id columns.</p>
  
  <p>For example if we enter (201, 301, 401) into (ID, Comp_Id, Cont_Id) respectively, the value 201_301_401 should be auto-generated in the Comp_Cont_Id column of the table.</p>
  
  <p>Is there a way to achieve it? If so please tell me.</p>