解決方法

Option 1 - Manually enter the project name

1. Enter the name of the project in the drop-down menu of the Connections dialog and click the plus icon.

Option 2 - Use custom SQL

1. From the Project drop-down list, select publicdata. 
2. From the Dataset drop-down list, select samples. 
3. Under Table, double-click 'New Custom SQL'. 
4. In the Edit Custom SQL dialog, enter a query using the syntax below and then click OK: 

   SELECT * FROM `project-id.dataset_name.table_name`

原因