Schema::tableExists

public Schema::tableExists($table)

public function tableExists($table) {
  $condition = $this->buildTableNameCondition($table);
  $condition->compile($this->connection, $this);
  // Normally, we would heartily discourage the use of string
  // concatenation for conditionals like this however, we
  // couldn't use db_select() here because it would prefix
  // information_schema.tables and the query would fail.
  // Don't use {} around information_schema.tables table.
  return (bool) $this->connection->query("SELECT 1 FROM information_schema.tables WHERE " . (string) $condition, $condition->arguments())->fetchField();
}