The difference between external tables and standard tables is in the following: on deleting an external table, the physical database object referenced by the external table is not deleted. Therefore, a standard table can be a source for building several external tables.
An external table is created if it is necessary to create new repository tables based on already existing server tables.
To create an external table in the object navigator:
In the web application click the Create button in the main menu and select the object type on the New Object side panel.
In the desktop application:
Execute one of the operations:
Select the Create > Table context menu item.
Click the New Object button in the Create group on the Home ribbon tab and select the Table item.
Select a type of object to be created on the Object Type page.
After executing the operations determine settings on the pages of the external table wizard:
Basic Settings/Basic Properties. It is used to set object name, identifier and comment.
Parameters. A list of parameters is created. The page is available only in the desktop application
Properties/Select Database. The database is specified, which tables are used to create external tables.
Select Tables. The tables are specified, which are used to create external tables in repository. The page is available only in the desktop application.
In the web application, when opening the external table wizard the additional pages are displayed:
Fields. Main external table field structure is created.
Indexes. A list of indexes is created, which will be further used to check data uniqueness. The setup is identical to table setup.
Constraints. A list of constraints is created, which will be used to automatically control entered data. The setup is identical to table setup.
Triggers. A list of triggers is created, which execute certain operations upon specified events. The setup is identical to table setup.
See also: