Information Systems for Business and Beyond (2019)

SELECT StudentMajor FROM STUDENT WHERE StudentName = ‘John Smith’;

The following query will list the total number of students in the STUDENT table: SELECT COUNT (*) FROM STUDENT; SQL can be embedded in many computer languages that are used to develop platform-independent web-based applications. An in- depth description of how SQL works is beyond the scope of this introductory text, but these examples should give you an idea of the power of using SQL to manipulate relational databases. Many DBMS, such as Microsoft Access, allow you to use QBE ( Query-by- Example ), a graphical query tool, to retrieve data though visualized commands. QBE generates SQL for you, and is easy to use. In comparison with SQL, QBE has limited functionalities and is unable to work without the DBMS environment.

Other Types of Databases

The relational database model is the most used database model today. However, many other database models exist that provide different strengths than the relational model. The hierarchical database model, popular in the 1960s and 1970s, connected data together in a hierarchy, allowing for a parent/child relationship between data. The document-centric model allowed for a more unstructured data storage by placing data into “documents” that could then be manipulated. Perhaps the most interesting new development is the concept of NoSQL (from the phrase “not only SQL”). NoSQL arose from the need to solve the problem of large-scale databases spread over several servers or even across the world. For a relational database to work properly, it is important that only one person be able to manipulate a Information Systems for Business and Beyond (2019) pg. 78

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