Question

Some people like describing their database structure in a simple textual way instead of using CREATE TABLE statements. A few example:

• Foreign key as Primary key
• Multiple Primary Keys as single foreign key
• How can I set up a database schema where there are two concurrent many-many relationships?
• primary key and foreign key
• How should I set up database tables for this order situation

Do you know about any software which converts this kind of shorthand notation to actual SQL statements?

Answer 1

Actually, I just finished creating a php script, which does exactly this, but I hope there is something more professional out there…

Demo of my converter:

http://simpleddl.orgfree.com

Example input:

= ID id P AI

person
  ID
  mother_id -> person
  father_id -> person
  !FK mother_id, father_id -> family U:C, D:C

family
  P female_id -> person
  P male_id   -> person

Output:

CREATE TABLE IF NOT EXISTS person (
   id         INT NOT NULL AUTO_INCREMENT,
   mother_id  INT NOT NULL,
   father_id  INT NOT NULL,
   PRIMARY KEY ( id )
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1;

CREATE TABLE IF NOT EXISTS family (
   female_id  INT NOT NULL,
   male_id    INT NOT NULL,
   PRIMARY KEY ( female_id, male_id )
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

ALTER TABLE person ADD FOREIGN KEY ( mother_id ) REFERENCES person( id );
ALTER TABLE person ADD FOREIGN KEY ( father_id ) REFERENCES person( id );
ALTER TABLE person ADD FOREIGN KEY ( mother_id, father_id ) REFERENCES family( female_id, male_id ) ON DELETE CASCADE ON UPDATE CASCADE;

ALTER TABLE family ADD FOREIGN KEY ( female_id ) REFERENCES person( id );
ALTER TABLE family ADD FOREIGN KEY ( male_id ) REFERENCES person( id );