在方格的下方，选择组成资料表主索引键的资料行。

In the grid beneath, choose the columns contributing to the table's primary key.

youdao

若要在不同的资料表之间切换，请使用每个面板中资料表方格上方的下拉式清单。

To switch between the different tables, use the drop-down list above the table grid in each panel.

youdao

表纸是用一系列小方格绘制而成的。

Graph paper is drawn with a series of small square.

youdao