Make sure that no objects are selected in Database Diagram designer by clicking anywhere within the designer except on an object.

确保没有在数据库关系图设计器中选择任何对象，方法是在该设计器中对象以外的任意位置单击。

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Make sure that no objects are selected in Database Diagram designer by clicking anywhere within the designer except on an object.

确保没有在数据库关系图设计器中选择任何对象，方法是在该设计器中对象以外的任意位置单击。

youdao