Wrong definition for MySQL string primary column

If you define a primary column, the attribute notnull is removed from the column definition because Doctrine assumes that primary columns are always not null.

Now suppose you have a schema like this, with a string primary column.

Client:
  columns:
    serial:    { type: string(50), notnull: true, primary: true }
    name:      { type: string(36), notnull: true }

That's fine, but causes problems with MySQL where the column is created with a default value of "" (empty string) and not <none>.

CREATE TABLE client (serial VARCHAR(50), name VARCHAR(36) NOT NULL, PRIMARY KEY(serial)) ENGINE = INNODB;

Note that the 2nd column is well defined and has <none> as default value (as seen from phpMyAdmin).

I attached a quick-workaround to disable the code which removes the notnull attribute from column definition.

After that the SQL code is like this:

CREATE TABLE client (serial VARCHAR(50) NOT NULL, name VARCHAR(36) NOT NULL, PRIMARY KEY(serial)) ENGINE = INNODB;