I am using node.js, Sequelize and MariaDB and I am running into the following error, which I am not sure how to resolve?

Error: Naming collision between attribute 'playlist' and association 'playlist' on model playlist_entry. To remedy this, change either foreignKey or as in your association definition

My Javascript:

Entities = function (settings, context) {

    sequelize = context.sequelize;

    var entities = {

        Playlist: this.sequelize.define('playlist', {
            name: Sequelize.STRING,
            description: Sequelize.STRING
        }),     

        PlaylistEntry: this.sequelize.define('playlist_entry', {
            playlist: Sequelize.INTEGER
            //track: Sequelize.INTEGER
        })

    };  

     entities.PlaylistEntry.belongsTo(
         entities.Playlist,
         { foreignKey: { name: 'fk_playlist' }});

    return entities;                    
}

My tables:

CREATE TABLE `playlist` (
  `id` int(11) unsigned NOT NULL,
  `name` varchar(255) NOT NULL,
  `description` varchar(255) DEFAULT NULL,
  `createdAt` timestamp NULL DEFAULT NULL,
  `updatedAt` timestamp NULL DEFAULT NULL,
  `external_id` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `playlist_entry` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `playlist` int(11) unsigned DEFAULT NULL,
  `track` int(11) unsigned DEFAULT NULL,
  `createdAt` timestamp NULL DEFAULT NULL,
  `updatedat` timestamp NULL DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `track_idx` (`track`),
  KEY `playlist_idx` (`playlist`),
  CONSTRAINT `fk_playlist` FOREIGN KEY (`playlist`) REFERENCES `playlist` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

I am using node.js, Sequelize and MariaDB and I am running into the following error, which I am not sure how to resolve?

Error: Naming collision between attribute 'playlist' and association 'playlist' on model playlist_entry. To remedy this, change either foreignKey or as in your association definition

My Javascript:

Entities = function (settings, context) {

    sequelize = context.sequelize;

    var entities = {

        Playlist: this.sequelize.define('playlist', {
            name: Sequelize.STRING,
            description: Sequelize.STRING
        }),     

        PlaylistEntry: this.sequelize.define('playlist_entry', {
            playlist: Sequelize.INTEGER
            //track: Sequelize.INTEGER
        })

    };  

     entities.PlaylistEntry.belongsTo(
         entities.Playlist,
         { foreignKey: { name: 'fk_playlist' }});

    return entities;                    
}

My tables:

CREATE TABLE `playlist` (
  `id` int(11) unsigned NOT NULL,
  `name` varchar(255) NOT NULL,
  `description` varchar(255) DEFAULT NULL,
  `createdAt` timestamp NULL DEFAULT NULL,
  `updatedAt` timestamp NULL DEFAULT NULL,
  `external_id` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `id` (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `playlist_entry` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `playlist` int(11) unsigned DEFAULT NULL,
  `track` int(11) unsigned DEFAULT NULL,
  `createdAt` timestamp NULL DEFAULT NULL,
  `updatedat` timestamp NULL DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `track_idx` (`track`),
  KEY `playlist_idx` (`playlist`),
  CONSTRAINT `fk_playlist` FOREIGN KEY (`playlist`) REFERENCES `playlist` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

• javascript
• node.js
• sequelize.js
• mariadb

• 4 You can specify an alias for the relationship with the key "as". docs.sequelizejs.com/en/latest/docs/associations – yBrodsky Commented May 9, 2016 at 17:42
• 1 Thanks, that helps: entities.PlaylistEntry.belongsTo(entities.Playlist, { as: 'Playlist', foreignKey: { name: 'fk_playlist' }});. – Andre M Commented May 9, 2016 at 17:58
• well but if you put the same name, isnt it the same? – yBrodsky Commented May 9, 2016 at 18:09
• True, but now Sequelize doesn't complain about the collision. Maybe a question of case? Would you recommend an alternative nomenclature here? – Andre M Commented May 9, 2016 at 18:16
• Nah, if it works its good I guess. Never had such a problem, though I remembered the documentation hence the suggestion. – yBrodsky Commented May 9, 2016 at 18:22

1 Answer 1

I faced exactly this problem while play with Sequelize, It's happened because the column name and reference name are same

Wrong Implementation

module.exports = (sequelize, DataTypes) => {
  const session = sequelize.define('session', {
    menteeId: DataTypes.INTEGER,
  }, {});

  session.associate = (models) => {
    session.belongsTo(models.user, {
      foreignKey: 'menteeId',
      as: 'menteeId',
      onDelete: 'CASCADE',
    });
  };
  return session;
};

Here the column name (menteeId) and alias name (menteeId) are the same, To resolve this you just need to change alias name

Correct Implementation

module.exports = (sequelize, DataTypes) => {
  const session = sequelize.define('session', {
    menteeId: DataTypes.INTEGER,
  }, {});

  session.associate = (models) => {
    session.belongsTo(models.user, {
      foreignKey: 'menteeId',
      as: 'MenteeId', // Changes applied here
      onDelete: 'CASCADE',
    });
  };
  return session;
};

In your case, you can do this

entities.PlaylistEntry.belongsTo(
    entities.Playlist,
    { 
    foreignKey: { name: 'fk_playlist' },
    as: 'PlayListAlias', // Appropriate name
    },
);