I think that the differences between Access and its competitors are in the way the technology is implemented. Most competitor database platforms (MySQL, Oracle Database, IBM's DB2 and Microsoft's SQL Server) are designed to be used as client-server databases where the database exists on a server and applications that access the data run on other computers like a user's laptop computer. Client-server database platforms provide the database application, while other functions provided by Microsoft Access, like database creation, database management, and data reporting require separate applications.
Microsoft Access is not designed to be used primarily as a client-server database, although it its data can be accessed by several users at the same time. The maximum number of concurrent users is limited compared to client-server database. There are other limitations, such as totaldatabase size, and row size that, while they seem large for the type of applications Access is targeted toward, those maximum sizes are small when compared to most client-server databases. Access can be programmed with Microsoft's VBA, but it does not implement a scripting language like most client-server databases. And Access does not implement stored procedures, database triggers, or transaction logging.
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