get source table values in civicrm_triggerInfo

Question

I have created below hook for trigger some values in my table.

Here how to get source table values that are being updated or inserted

function history_civicrm_triggerInfo(&$info, $tableName) {
  $sourceTable = 'civicrm_membership_log';

  $sql = "
    INSERT INTO `civicrm`.`civicrm_membershipperiod` 
(`id`, `membership_id`, `start_date`, `end_date`) VALUES (NULL, '1', '2017-07-03', '2018-07-03');";


  $info[] = array(
      'table' => $sourceTable,
      'when' => 'AFTER',
      'event' => 'INSERT',
      'sql' => $sql,
  );
  $info[] = array(
      'table' => $sourceTable,
      'when' => 'AFTER',
      'event' => 'UPDATE',
      'sql' => $sql,
  );
}

Based on the source table value I have to rewrite the query $sql

Answer 1

I'm not familiar with this hook, but the manual seems to suggest that OLD.column_name and NEW.column_name can be used to access old and new values respectively.