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A relational database is a collection of data items organized as a set of formally described tables from which data can be accessed or reassembled in many different ways without having to reorganize the database tables.
The standard user and application program interface to a relational database is the structured query language (SQL). SQL statements are used both for interactive queries for information from a relational database and for gathering data for reports.
In addition to being relatively easy to create and access, a relational database has the important advantage of being easy to extend. After the original database creation, a new data category can be added without requiring that all existing applications be modified.
A relational database is a set of tables containing data fitted into predefined categories. Each table (which is sometimes called a relation) contains one or more data categories in columns. Each row contains a unique instance of data for the categories defined by the columns. For example, a typical business order entry database would include a table that described a customer with columns for name, address, phone number, and so forth. Another table would describe an order, with columns for product, customer, date, sales price, and so forth. A user of the database could obtain a view of the database that fitted the user's needs. For example, a branch office manager might like a view or report on all customers that had bought products after a certain date. A financial services manager in the same company could, from the same tables, obtain a report on accounts that needed to be paid.
Caravan Database The Caravan Database Manager is also a relational database. The concept of relation is handled in a different way in Caravan. Unlike other databases, the record number in a Caravan table is unique. Each record in a table has a unique record id. Even if a record is deleted the record space is reused but the record id is changed.
In Caravan database, the record number of the master table acts as the primary key. Other tables use this record number to establish a relation. Relation can be established between multiple tables.
Creating relational tables When you create a table, along with field types, you also get a list of tables with which you can set relations. In Caravan, a relation is set between the field and the table.
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