Connection::escapeField

public Connection::escapeField($field)

public function escapeField($field) {
  $escaped = parent::escapeField($field);

  // Remove any invalid start character.
  $escaped = preg_replace('/^[^A-Za-z0-9_]/', '', $escaped);

  // The pgsql database driver does not support field names that contain
  // periods (supported by PostgreSQL server) because this method may be
  // called by a field with a table alias as part of SQL conditions or
  // order by statements. This will consider a period as a table alias
  // identifier, and split the string at the first period.
  if (preg_match('/^([A-Za-z0-9_]+)"?[.]"?([A-Za-z0-9_.]+)/', $escaped, $parts)) {
    $table = $parts[1];
    $column = $parts[2];

    // Use escape alias because escapeField may contain multiple periods that
    // need to be escaped.
    $escaped = $this->escapeTable($table) . '.' . $this->escapeAlias($column);
  }
  else {
    $escaped = $this->doEscape($escaped);
  }

  return $escaped;
}