protected function pushColumns()
    {
        if( !$this->columns || $this->columns == '*' ) {
            $this->parts[] = '*';
        } else if( is_array($this->columns) ) {
            $cols = array();
            foreach( $this->columns as $col ) {
                $cols[] = $this->quoteIdentifierIfNotExpression($col);
            }
            $this->parts[] = join(', ', $cols);
        } else if( is_string($this->columns) ) {
            $this->parts[] = $this->quoteIdentifierIfNotExpression($this->columns);
        } else if( $this->columns instanceof Expression ) {
            $this->parts[] = (string) $this->columns;
        }
    }
protected function pushColumns()
    {
        if( !$this->columns || $this->columns == '*' ) {
            $this->parts[] = '*';
        } else if( is_array($this->columns) ) {
            $cols = array();
            foreach( $this->columns as $col ) {
                $cols[] = $this->quoteIdentifierIfNotExpression($col);
            }
            $this->parts[] = join(', ', $cols);
        } else if( is_string($this->columns) ) {
            $this->parts[] = $this->quoteIdentifierIfNotExpression($this->columns);
        } else if( $this->columns instanceof Expression ) {
            $this->parts[] = (string) $this->columns;
        }
    }
protected function pushColumns ( ) { if ( ! $ this -> columns || $ this -> columns == '*' ) { $ this -> parts [ ] = '*' ; } else if ( is_array ( $ this -> columns ) ) { $ cols = array ( ) ; foreach ( $ this -> columns as $ col ) { $ cols [ ] = $ this -> quoteIdentifierIfNotExpression ( $ col ) ; } $ this -> parts [ ] = join ( ', ' , $ cols ) ; } else if ( is_string ( $ this -> columns ) ) { $ this -> parts [ ] = $ this -> quoteIdentifierIfNotExpression ( $ this -> columns ) ; } else if ( $ this -> columns instanceof Expression ) { $ this -> parts [ ] = ( string ) $ this -> columns ; } }
Push columns onto parts

@return void
Push columns onto parts