Code example for custom Entity

drupal-entity-code.php

<?php 

/**
* Implements hook_entity_info().
*/
function dance_code_entity_info() {
  $ents['proficiency'] = array(
    'label' => t('Proficiency Status'),
    'plural label' => t('Proficiency Statuses'),
    'fieldable' => TRUE,
    'base table' => 'dance_proficiency',
    'entity keys' => array(
      'id' => 'dpid',
      //'label' => 'title',
      ),
    //'bundle keys' => array(),
    //'bundles' => array(),
    'entity class' => 'Entity',
    'controller class' => 'EntityAPIController',
    'admin ui' => array(
      'path' => 'admin/dance/proficiency',
      ),
    'module' => 'dance_code',
    'access callback' => 'dance_code_proficiency_access',
    'uri callback' => 'dance_code_proficiency_uri',
  );
  return $ents;
}

/**
* Implements hook_entity_property_info().
*/
function dance_code_entity_property_info() {
  $info = array();
  // Add meta-data about the basic node properties.
  $properties = &$info['proficiency']['properties'];
  $properties['dpid'] = array(
    'label' => t("DANCE Proficiency ID"),
    'type' => 'integer',
    'description' => t("The unique ID of the node."),
    'schema field' => 'dpid',
  );
  $properties['user'] = array(
    'label' => t("Learner"),
    'type' => 'user',
    'description' => t("The Learner associated with the proficiency status."),
    // These are "default", but you need to add them anyway (ie NOT default)
    'setter callback' => 'entity_property_verbatim_set',
    'getter callback' => 'entity_property_verbatim_get',
    'setter permission' => 'Administer Proficiency',
    'required' => TRUE,
    'schema field' => 'uid',
  );
    $properties['assessment1'] = array(
    'label' => t("Assessment number 1"),
    'type' => 'proficiency_assessment',
    'type' => 'node',
    'bundle' => 'proficiency_assessment',
    'description' => t("Node reference to first proficiency assessment"),
    'setter callback' => 'entity_property_verbatim_set',
    'getter callback' => 'entity_property_verbatim_get',
    'setter permission' => 'Administer Proficiency',
    'schema field' => 'assessment1',
  );
  $properties['assessment2'] = array(
    'label' => t("Assessment number 2"),
    'type' => 'node',
    'bundle' => 'proficiency_assessment',
    'description' => t("Node reference to second proficiency assessment"),
    'setter callback' => 'entity_property_verbatim_set',
    'getter callback' => 'entity_property_verbatim_get',
    'setter permission' => 'Administer Proficiency',
    'schema field' => 'assessment2',
  );
  $properties['sent_reminder'] = array(
    'label' => t("Was learner Sent Reminder?"),
    'type' => 'boolean',
    'description' => t("boolean: whether learner has been sent reminder."),
    'setter callback' => 'entity_property_verbatim_set',
    'getter callback' => 'entity_property_verbatim_get',
    'setter permission' => 'Administer Proficiency',
    'schema field' => 'sent_reminder',
  );
  return $info;
}

drupal-entity-install.php

<?php

/**
 * Implements hook_schema().
 */

function dance_code_schema() { 
 $schema['dance_proficiency'] = array(
   'description'=>'The table for storing DANCE coding sheets.',
   'fields' => array(
      'dpid' => array(
         'description' => 'The primary key',
         'type' => 'int',
         'unsigned' => TRUE,
         'not null' => TRUE,
       ),
      'uid' => array(
         'description' => 'The id of the User',
         'type' => 'int',
         'unsigned' => TRUE,
         'not null' => TRUE,
       ),
      'sent_reminder' => array(
        'description' => 'boolean: whether user has been sent reminder 9 months for prof, 3 months for np',
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 0,
      ),
      'assessment1' => array(
         'description' => 'ID of the first assessment',
         'type' => 'int',
         'unsigned' => TRUE,
         'not null' => FALSE,
       ),
      'assessment2' => array(
         'description' => 'ID of the second assessment',
         'type' => 'int',
         'unsigned' => TRUE,
         'not null' => FALSE,
       ),
      'is_proficient' => array(
        'description' => 'boolean: whether user is proficient',
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => FALSE,
      ),
      'created' => array(
         'description' => 'The creation date timestamp',
         'type' => 'int',
         'unsigned' => TRUE,
         'not null' => TRUE,
       ),
      'active_date' => array(
         'description' => 'The date this proficiency was set to active',
         'type' => 'int',
         'unsigned' => TRUE,
         'not null' => FALSE,
       ),
      'active' => array(
         'description' => 'Whether this is the most recent Proficiency decision',
         'type' => 'int',
         'unsigned' => TRUE,
         'not null' => FALSE,
       ),
   ),
   'primary key' => array('dpid'),
  );
  return $schema;
}