Question

I have the following table:

CREATE TABLE IF NOT EXISTS `customer_list` (
   `id` INT AUTO_INCREMENT,
   `first_name` char(4) NOT NULL,
   `last_name` varchar(80) NOT NULL,
   `phone` varchar(50) NOT NULL,
   `province` varchar(50) NOT NULL,
   `country` varchar(30) NOT NULL,
   `start_date` TIMESTAMP NOT NULL,
   `end_date` TIMESTAMP NOT NULL,
   PRIMARY KEY (id)
 ) ENGINE=MyISAM DEFAULT CHARSET=utf8;

I want to be able to insert into this table with the only restriction being that first_name, last_name and phone CANNOT be the same. If they are the same I want some sort of error returned to warn the end user that the record already exists – No insert/update/replace action is performed.

The key here is the INSERT statement must somehow check 3 fields for duplication. The error must only return if ALL 3 fields are duplicates. IE. 1 or 2 out of the 3 are allowed to be duplicates and still be entered.

Is this possible with one INSERT statement?

Answer 1

Try:

alter table customer_list add unique index(first_name, last_name, phone);