Mysql-Creating a Derived Data Column
Frequently we query our database for a value but then have to always do the same manipulation on it before we can use it. Well it can often be useful to do this “once” in the database and then store the manipulated value in a separate column of the database.
Here is a very simple example
INSERT INTO tbl_name (col1,col2) VALUES(15,col1*3.14159);
Where col2 is set to the value of col1*pi
You could also do more complex calculation/filtering/shortening in your code eg php,ASP etc
Tags: column, Data, database, Derived, Frequently, insert, INTO, manipulated, MySQL, once, separate, useful, values