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Step 4:  In the next column, select and use the field on which information is required, which in this case is Quantity.
        Step 5:  In the Function row, click to open the drop-down list and select the option Sum.

















        Step 6:  Press Ctrl + S keys to save the query.
        Step 7:  Double-click on the query name to run the query.
                Notice that the sum of number of items in each category is shown upon execution of the query.











                 STRUCTURED QUERY LANGUAGE(SQL)
        As you know that a relational database is a collection of tables. A user may insert new records/rows, delete records,
        and modify records in these tables. The language used to perform all these operations is known as query language. A
        Database Management System (DBMS) used to manage Relational Databases is called RDBMS (Relational Database
        Management System). Many RDBMS software, such as MySQL, Microsoft SQL Server, PostgreSQL, Oracle, etc., allow
        us to create a database consisting of relations and link one or more relations for efficient querying to store, retrieve,
        and manipulate data in that database.
        Structured Query Language (SQL) is the standard language for managing relational databases and performing various
        operations on the data in the tables. It would enable us to store, retrieve, and manipulate data in the tables.

        SQL is a high-level interactive language that allows users to specify what is required to be done in the form of queries.
        Unlike other high-level languages, we do not need to specify how the SQL operations are implemented.

        OpenOffice Base provides SQL view to write queries. We can access it by clicking on the Create Query in SQL View
        command under the Tasks pane.












        After writing the query, save the query. Close the query design window. Double-click on the query name under the
        Tasks pane. The result of the query will be displayed.











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