Display and Maintenance of Hierarchically Structured Tables (TOPIC, LOCATION): OracleForm "hierMDB"

General Remarks

Some of the CERA Tables are hierarchically organized. This means, that every item (record) contains a reference to a preceeding record of the same table. Only the root record has no predecessor, it references itself.
For the display (normal operator) and maintenance (administrator) of these tables, the OracleForm "hierMDB" was created. So the treelike sturcture can be inspected and changed.
The form hierMDB gives access to both, the TOPIC and the LOCATION table. A view "HIERARCHY" is generated to project the selected table on the form's structure. To start the beginning level for the left subtable has to be selected (usually level 1). Clicking on any item at any level makes the subordinate items of the following level visible in the next right subtable.

Operator's Usage of the Form

Button "change table"

This button changes the table displayed in the hierarchy from TOPIC to LOCATION and vice versa.

Button "number of references"

Gives out the number of references to the lastly doubleclicked item (in the console at lower left of the window), i.e. the number of CERA Entries that are linked to the item.

Button "HELP"

Displays a little help text, that summarizes the task of every button.

Button "EXIT"

Exits the form hierMDB.

Administrator's Usage of the Form

The administration buttons are disabeled, except for administrational use.

Button "move link"

This button is to move an item to another place in the hierarchical tree. When you doubleclick an item it will be moved below the item you doubleclick next (there will be a warning before) by changing its pointer. You will have to issue a new query (select the uppermost level) to make it visible. The level information of the moved item will not be changed.

Button "update all level data"

As moving items does not change their level information, inconsistencies will arise. Updating all level data sets all levels to "1predecessor's level", starting with level one.

Button "re-reference"

This button will change all links from CERA Entries to the firstly doubleclicked item into links to the lastly doubleclicked item. So the first item will remain without links.

Button "new item"

Calls a new form to enter a new item. The new item will be visible after a new selection of the uppermost level with one of the level buttons. It will be linked to the root item, so it usually will have to be moved.

Deleting Items

This can be done by "record, remove" in the OracleForms menue, if there are no more references from CERA Entries to the item.

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Last change: Fri May 28 21:35:14 NFT 1999