What is SQL*Plus and where does it come from?

SQL*Plus is a command line SQL and PL/SQL language interface and reporting tool that ships with the Oracle Database Client and Server. It can be used interactively or driven from scripts. SQL*Plus is frequently used by DBAs and Developers to interact with the Oracle database.

If you are familiar with other databases, sqlplus is equivalent to "sql" in Ingres, "isql" in Sybase and SQLServer, "db2" in IBM DB2, "psql" in PostgresQL, and "mysql" in MySQL.

SQL*Plus's predecessor was called UFI (User Friendly Interface). UFI was included in the first Oracle releases up to Oracle v4. The UFI interface was extremely primitive and, in today's terms, anything but user friendly. If a statement was entered incorrectly, UFI issued an error and rolled back the entire transaction (ugggh).