Adding and deleting tables in a query

To add some extra tables to a query:
1. In the Query Editor window, select Add Table from the Query menu to bring up the Add Data dialog. See the dialog.
2. From the All Data box, select tables, views, queries, imported SQLs, stored procedures and user defined data sources that you want to use in the query, then click to add them into the Selected Data box. When two resources (for example, a table and a view) use the same name, they cannot be added to the right box at the same time, and when a table is already contained in a query, you cannot add the table and the query at the same time.
  To remove unwanted resources from the Selected Data box, select them and click .
3. Click OK to add the selected resources to the current query. When a query, imported SQL, stored procedure or user defined data source is added, it will be added as a single table with all of its columns.
4. Click Arrange Tables in the Query menu to organize the tables.
5. Select the required columns in each table. The columns will be displayed in the criteria panel of the Query Editor.
To remove tables from a query:
1. Select the table that you want to delete in the Query Editor window.
2. Click Delete Table on the Query menu.
3. Repeat the above steps to delete other tables.

Notes:

For tables added to a query, you can decide whether or not show the full name of the fields (with table names) by checking the option Show Mapping Names on the Query menu.
After deleting a table from a query, any joins based on the table will be moved.
In the criteria panel, if you do not want to show the table names for the selected columns, you can uncheck Show Table Names on the Query menu.
To delete a column in a table, select the column in the criteria panel and click Delete Column on the Column menu. You can also undo the deletion by finding the field in the table and placing a check mark beside it.