function poll_update_7001 in Drupal 7

Use the poll_choice primary key to record votes in poll_votes rather than the choice order. Rename chorder to weight.

Rename {poll_choices} table to {poll_choice} and {poll_votes} to {poll_vote}.

File

modules/poll/poll.install, line 157

Install, update and uninstall functions for the poll module.

Code

function poll_update_7001() {

  // Add chid column and convert existing votes.
  db_add_field('poll_votes', 'chid', array(
    'type' => 'int',
    'unsigned' => TRUE,
    'not null' => TRUE,
    'default' => 0,
  ));
  db_add_index('poll_votes', 'chid', array(
    'chid',
  ));
  db_update('poll_votes')
    ->expression('chid', Database::getConnection()
    ->prefixTables('COALESCE((SELECT chid FROM {poll_choices} c WHERE {poll_votes}.chorder = c.chorder AND {poll_votes}.nid = c.nid), 0)'))
    ->execute();

  // Delete invalid votes.
  db_delete('poll_votes')
    ->condition('chid', 0)
    ->execute();

  // Remove old chorder column.
  db_drop_field('poll_votes', 'chorder');

  // Change the chorder column to weight in poll_choices.
  db_change_field('poll_choices', 'chorder', 'weight', array(
    'type' => 'int',
    'not null' => TRUE,
    'default' => 0,
    'size' => 'tiny',
  ));
  db_rename_table('poll_votes', 'poll_vote');
  db_rename_table('poll_choices', 'poll_choice');
}