Data is always structure and content, syntax and semantics. In the context of databases, these are tables, relationships between tables, queries and their results. It cannot be said that the prevailing idea of relational databases is an ideal, but it is practical, convenient and allows you to describe any area of application.
If the database is a collection of tables, then the database management system (DBMS) is the support of several databases at once and the provision of appropriate functionality for each of them in terms of administration, operation and reading. Over time, DBMSs acquired many very specific functions, which are considered to be the de facto standard, and received their own language for describing, working, and selecting.
Basic DBMS functionality
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