MySQL auto-increment based on group

Question

The problem is related to autoincrement with mysql. What I\'m trying to achieve is to increment an ID value based on the customer number. So basically i insert data sets without

Answer 1

You could procedurally do this using a stored procedure, which I won't elaborate on (unless requested) as it isn't a simple query (as you're asking for).

A hacky solution would be to bulk insert into a new joining table:

CREATE TABLE auto_inc_customer_id (
   id INT UNSIGNED NOT NULL AUTO_INCREMENT,
   customer_id INT UNSIGNED NOT NULL, -- Could/should add a FK constraint
   PRIMARY KEY (id)
) ENGINE=innodb;

INSERT INTO auto_inc_customer_id SELECT NULL, DISTINCT(Customer) FROM YourExistingTable;

See: http://dev.mysql.com/doc/refman/5.7/en/ansi-diff-select-into-table.html