Entity having two entities of the same type

Question

I'm programming a small game and a database representing Players and Matches.

A player has a name, a player ID and a rank. A match has an ID, and two players.

Player

• * id (bigint)
• name (string)
• playerID (string)
• rank (integer)

Match

• * id (bigint)
• matchID (string)
• playerOne (Player)
• playerTwo (Player)

I would like to have a "matches" relationship in a Player, but how do I have an entity having two entities of same type and what type relationship should I use?

I tried a one-to-one relationship, but the UNIQUE condition it created is a problem.

Answer 1

If you want to easily find all matches per player you will need to use a ManyToMany relationship. The following is a simplified snippet of what the classes would look like.

class Player {

    /**
     * @ORM\ManyToMany(targetEntity="Match", mappedBy="players")
     */
    protected $matches;

}

class Match {

    /**
     * @ORM\ManyToMany(targetEntity="Player", inversedBy="matches")
     */
    protected $players;

}

Then you run the following command from the root directory:

php app/console doctrine:generate:entities Your/AwesomeBundle/Entity

And you will be able to use methods such as:

Match::getPlayers()
Match::addPlayer()
Player::addMatch() // probably will have an 'e' at the end of the word match
Player::getMatches() // which is the one that will give you all matches of a user

You will need to restrict the number of players per match in your code.