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The Relations dialog box gives four options for maintaining referential integrity. These options are as follows:
                      •   No action: This option, set as the default, prohibits users from updating or deleting any record in the
                         master table if related records exist in the transaction table.
                      •   Update cascade: This option enables users to update or delete the referenced field, causing all related
                         records in any of the transaction tables to also be updated or deleted.
                      •   Set NULL: With this option, if the master record is deleted or updated, all related fields are assigned a NULL
                         value.
                      •   Set default: This option assigns a predetermined default value to all related fields if the master record is
                         deleted or updated.
              Step 2:  Select the tables in the Tables Involved section
              Step 3:  Select the fields from the tables in the Fields Involved section to modify the relationship.
              Step 4:  Click on the OK button.

              Deleting the Relationship

              Relationship once created can be easily removed by deleting them using the given steps:
              Step 1:  Click on Tools menu. A drop-down menu will appear.
              Step 2:  Select Relationships option from the menu. The Relation window will appear.
              Step 3:  Right-click on the relationship thread and select the Delete option.




























              The relationship between tables will be removed thus showing that now the two tables are not related.


                                      Create  a database  Library with the tables -  Books in stock, Books issued,  Books lost/
                                      damaged.
                       uiz Bee        1.  Design the structure of all the 3 tables with the primary key, foreign key.
                                      2.  Link the three tables and name the relationships, if possible, between different tables in
                                        a database.
                                      3.  Can a referential integrity be set between Books in stock and Books issued? If yes, explain
                                        the concept with reference to the given two tables.
                                      4. Give the steps to delete a relationship in the LibreOffice Base.








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