You can have a column called Other Condition in the decision table where you can specify a full blown condition (including nested AND and OR conditions).
Locate the ruleset, expand the ruleset node, the Rules folder and double-click a decision table node.
For more information, see Locating the Ruleset
or
Locate the flow ruleset , expand the flow ruleset node, the Decision Tables folder and double-click a decision table node.
For more information, see Locating the Flow Ruleset
You can also expand the Decision Tables folder in the Outline view and choose a decision table node.
In the decision table editor, choose the Condition button.
In the menu that appears, choose Add Other Condition .
Save the changes.
You can also add an other condition when you create a decision table as follows:
On the Select the Conditions screen of the Decision Table Wizard select the Table has Other Condition checkbox.
To add a condition, double-click a cell under the Other Condition header in the Decision Table.
In the editor that appears, choose .
The default condition: System.currentTimeMillis() Greater Than 1208497381741 appears.
To edit the default condition:
Choose the LHS value: System.currentTimeMillis() and in the drop down menu choose a definition or alias.
Choose the comparator: Greater than and choose a comparator in the drop down menu.
More Information: List of Return Types and Comparator Choices for Conditions
Choose the RHS value after the comparator and in the drop down menu choose a definition or alias.
Press Alt + Enter and save the changes.
In the Decision Table editor, choose the Condition button and choose Rename Other Condition .
In he dialog box that appears, enter an alternative name and choose OK .
To add nested conditions, repeat the steps and add more conditions. The conditions appear within parentheses and are combined by the logical operator: and . You can change the logical operator by clicking it.