SQLPlus is the first client of the Oracle Database.
SQL*Plus does not have a SQL or PL/SQL command parser. It scans the first few keywords of each new statement to determine the command type, SQL, PL/SQL or SQL*Plus.
On windows, there is two versions of SQL*Plus :
- a GUI one (sqlplusw.exe) Officialy deprecated in the next release of Oracle.
- a DOS based character-mode one (sqlplus.exe)