Note: Background information on Cascade rules can be found in the About Cascade Rules document.

The Cascade Rule Join Condition dialog box exists to collect information on the join condition of Cascade rules. This dialog box is the second and final dialog box of a series when a new Cascade rule is created and is also used to edit the join condition for an existing Cascade rule.

In order to use the Cascade Rule dialog box, the columns on which the two tables are to be joined must be known. The join column can be the same as the column to be synchronized. If this is the case, the information being used to update the parent and child columns must not previously exist in the child table column. If the column to be synchronized is part of the join condition and if the data being used to update that column previously exists in the child column it is possible for the synchronization process to associate rows wrongly because of conflicts within the join. There is no such issue if the column to be synchronized is not part of the join condition - in that case any substitution values can be used - even ones that already exist in the child table.

The Cascade Rule Join Condition Dialog Box

The panels on the far left and right sides of the dialog box list the columns for the parent and child table involved in the rule. The central two rows of six fields are used for the column join conditions. Each Cascade rule can join on a maximum number of six conditions.

To the side of each field is a delete button and an up-down button pair which can be used to edit the join information for a rule. Above the join condition fields is an icon containing a large letter I. A green icon indicates that the columns present are indexed, a red icon indicates that the columns are not indexed. If the child table is large it is very important that the join columns of the child table in the relationship are indexed otherwise the cascade of data will be very slow for that rule.

The Via DB Link Field If the schema and table to be updated via the Cascade rule are located on a different database than the source schema and table then the cascade operation will proceed via a database link. The database link must be located in the source schema and be pointed at the target schema. The DB link can be named here before it is created however, it must exist before the masking set runs. A DB link is not required (and will be ignored) if both the source and target schema are located in the same database.

Using the Cascade Rule Join Condition Dialog Box

Step 1

Select the first join column for the parent table in the left hand panel. Similarly, select the equivalent join column for the child table in the right hand panel.

Step 2

Once each column is selected click on the Add button beside the column list box. This will move the column name up into the uppermost empty column field in the center of the dialog box.

Step 3

If there are no more join columns required for this rule then proceed to step 4 otherwise select the next pair of matching columns on each side and repeat Step 2. Any subsequently added join column pairs will be inserted in the first empty slot in the central column fields.

Step 4

At this point the construction of the Cascade rule is complete. Click on the Save Rule button to store the rule. The join condition for Cascade rules can easily be edited at a later time.