function recommender_schema in Recommender API 7.5

Same name and namespace in other branches

1. 5 recommender.install \recommender_schema()
2. 6.3 recommender.install \recommender_schema()
3. 6 recommender.install \recommender_schema()
4. 6.2 recommender.install \recommender_schema()
5. 7.6 recommender.install \recommender_schema()
6. 7.3 recommender.install \recommender_schema()
7. 7.4 recommender.install \recommender_schema()

Implements hook_schema().

Note: One big difference compared to previous release is to remove the {recommender_app} table and simply uses a varchar field 'recommender' to distinguish between different applications. Such a design violates database normal forms, and it might have negative effects on performance. But it does simplifies programing logic. Let's see if it needs change in the feature.

File

./recommender.install, line 14

Installation file for the Recommender API module. Note: Not compatible with 6.x releases. Please uninstall 6.x releases before installing the D7 release.

Code

function recommender_schema() {
  $schema = array(
    // table to save preference scores
    'recommender_preference' => array(
      'description' => 'This is the main table to save preference data. The structure is the same to prediction/similarity table.',
      'fields' => array(
        // this id might be redundant.
        'id' => array(
          'description' => 'Unique index for each preference data',
          'type' => 'serial',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'recommender' => array(
          'description' => 'This field distinguishes different recommender applications.',
          'type' => 'varchar',
          'length' => 20,
          'not null' => TRUE,
        ),
        'source_id' => array(
          'description' => 'The first source entity_id. This is usually user id.',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'target_id' => array(
          'description' => 'The target entity_id. This is usually item id.',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'score' => array(
          'type' => 'float',
          'size' => 'normal',
          'not null' => FALSE,
          'description' => 'The preference score. Higher score means source prefers target more.',
        ),
        'updated' => array(
          'description' => 'The Unix timestamp this preference is last changed',
          'type' => 'int',
          'not null' => TRUE,
          'default' => 0,
        ),
      ),
      'primary key' => array(
        'id',
      ),
      // note that this is not unique indexes.
      'indexes' => array(
        'recommender' => array(
          'recommender',
        ),
        'index_key' => array(
          'recommender',
          'source_id',
          'target_id',
        ),
      ),
    ),
    // table to save similarity scores
    'recommender_similarity' => array(
      'description' => 'This is the main table to save similarity data. The structure is the same to prediction table, but stores different data',
      'fields' => array(
        // this id might be redundant.
        'id' => array(
          'description' => 'Unique index for each similarity pair',
          'type' => 'serial',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'recommender' => array(
          'description' => 'This field distinguishes different recommender applications.',
          'type' => 'varchar',
          'length' => 20,
          'not null' => TRUE,
        ),
        'source_id' => array(
          'description' => 'The first source entity_id. The type is the same to the target entity',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'target_id' => array(
          'description' => 'The target entity_id. The type is the same to the source entity',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'score' => array(
          'type' => 'float',
          'size' => 'normal',
          'not null' => FALSE,
          'description' => 'Similarity score. The bigger, the more similar',
        ),
        'updated' => array(
          'description' => 'The Unix timestamp this similarity is last changed',
          'type' => 'int',
          'not null' => TRUE,
          'default' => 0,
        ),
      ),
      'primary key' => array(
        'id',
      ),
      // note that this is not unique indexes.
      'indexes' => array(
        'recommender' => array(
          'recommender',
        ),
        'index_key' => array(
          'recommender',
          'source_id',
          'target_id',
        ),
      ),
    ),
    // table to save predictions
    'recommender_prediction' => array(
      'description' => 'This is the main table to save prediction data. The structure is the same to similarity table, but here source and target are different type of entities',
      'fields' => array(
        // this id might be redundant.
        'id' => array(
          'description' => 'Unique index for each prediction link',
          'type' => 'serial',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'recommender' => array(
          'description' => 'This field distinguishes different recommender applications.',
          'type' => 'varchar',
          'length' => 20,
          'not null' => TRUE,
        ),
        'source_id' => array(
          'description' => 'The entity_id for which the prediction is generated. This is usually user id',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'target_id' => array(
          'description' => 'The entity_id of the target prediction. This is usually item id.',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'score' => array(
          'type' => 'float',
          'size' => 'normal',
          'not null' => FALSE,
          'description' => 'The prediction score. Higher score means source prefers target more.',
        ),
        'updated' => array(
          'description' => 'The Unix timestamp this prediction is last changed',
          'type' => 'int',
          'not null' => TRUE,
          'default' => 0,
        ),
      ),
      'primary key' => array(
        'id',
      ),
      // note that this is not unique indexes.
      'indexes' => array(
        'recommender' => array(
          'recommender',
        ),
        'index_key' => array(
          'recommender',
          'source_id',
          'target_id',
        ),
      ),
    ),
    'recommender_preference_staging' => array(
      'description' => 'This table stages user-item preference data if it is from a SQL query. Should get purged before app running',
      'fields' => array(
        'source_id' => array(
          'description' => 'The entity_id of the owner of the preference. This is usually user id',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'target_id' => array(
          'description' => 'The entity_id of the target of the preference. This is usually item id.',
          'type' => 'int',
          'size' => 'normal',
          'unsigned' => TRUE,
          'not null' => TRUE,
        ),
        'score' => array(
          'type' => 'float',
          'size' => 'normal',
          'not null' => FALSE,
          'description' => 'The preference score. Higher score means source prefers target more.',
        ),
        'updated' => array(
          'description' => 'The Unix timestamp this preference is last changed',
          'type' => 'int',
          'not null' => TRUE,
          'default' => 0,
        ),
      ),
      'primary key' => array(
        'source_id',
        'target_id',
      ),
    ),
  );
  return $schema;
}