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Step 5:  Click on the Close button to close the Add Tables dialog box.
        Step 6:   Now press the mouse button on Subject Code in SUBJECTS table and drag Subject Code in TEACHERS table.
                Release the button to see a line drawn as shown below:





























        Step 7:   Click on File menu and select Close button. The relationship created will be saved and implemented in the
                tables.

        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 Relationship window will appear.
        Step 3:  Right-click on the relationship thread and select the Delete option.

                The thread between the tables will be removed thus showing that now the two tables are not related.
        Step 4:  Remove the tables from the Relation Design window.
        Step 5:  Close the window.


                                Create a database Library with the tables - Books in stock, Books issued, Books lost/
                 uiz Bee        damaged.

                                •  Design the structure of all the 3 tables with the primary key, foreign key.
                                •   Link the three tables and name the relationships if possible between different tables in
                                  a database.
                                •   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.
                                •  Give the steps to delete a relationship in the OpenOffice Base.





                WHAT IS A QUERY?

        Query is a set of commands that generates a request to access or manipulate data in a table. A query is of great help
        when information is required to be extracted from different tables. It uses the process of filtering the information
        based on the criteria from the table.


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