code: public function from(
          $table,
          /*# string */ $tableAlias = ''
      )/* : FromInterface */ {
          if (is_array($table)) {
              foreach ($table as $key => $val) {
                  if (is_int($key)) {
                      $key = $val;
                      $val = '';
                  }
                  $this->from($key, $val);
              }
          } else {
              // overwrite exisiting same table
              $key = array_search($table, $this->clause_table, true);
              if (false !== $key) {
                  unset($this->clause_table[$key]);
              }
  
              if (empty($tableAlias)) {
                  $this->clause_table[] = $table;
              } else {
                  $this->clause_table[(string) $tableAlias] = $table;
              }
          }
          return $this;
      }
docs: {@inheritDoc}