generally call them relational databases. 6 You might have heard of PostgreSQL, MySQL, Oracle, SQLite, MariaDB, SQL Server. Those are all relational databases. Note the “SQL” in their name. They are as its latest version, 2019. SQL is implemented in many popular DBMS: Postgres, MySQL, Oracle, SQLite, MicroSoft SQL Server, and many more. 8 Each different database implements the standard, or a particular absolutely use those, as long as you know that switching DBMS to a different one, say from PostgreSQL to SQLite, could be problematic if those nonstandard types (and features) are used. This is the syntax to