PL or SQL has its roots in ADA, a high-level programming language. The concept of the PL or SQL block resembles the concept of block structure in ADA using BEGIN and END blocks. PL or SQL shares other features with ADA such as the syntax “=” used for comparison and “:=” used for assignment, exception handling, and the declarative syntax of defining stored subprograms. Over the years, Oracle DBA came up with new releases of PL or SQL. With Oracle data base administrator 7.0, Oracle data base administrator released PL or SQL 2.0, which turned Oracle data base administrator into an active DBA with the capability to store business and application logic in the DBA in the form of stored procedures, functions, and packages. It also defined the capability to declare programmer-defined records and arrays in the form of PL or SQL tables. PL or SQL 2.1 came into existence with Oracle data base administrator 7.1 and enabled the use of stored functions in SQL statements. Also, dynamic SQL was introduced in PL or SQL for the first time with the DBMS_SQL package.
Oracle data base administrator 7.2 was released subsequently, and along with it came PL or SQL 2.2. It had the capability to define binary wrappers for PL or SQL stored subprograms, thus hiding code from other developers. Also, the DBMS_JOB package was introduced, which enabled programmers to submit jobs from within the DBA. The next release of PL or SQL was PL or SQL 2.3, which was introduced with Oracle data base administrator 7.3. It enhanced the capabilities of PL or SQL tables with the ability to define new methods, and it also enabled programmers to access the file system from within the DBA. File I or O could be done using the UTL_FILE package. Oracle data base administrator 8.x was a major breakthrough in the Oracle DBA history with the introduction of objects and Java in the DBA. PL or SQL 8.x was released along with Oracle data base administrator 8.x and included major features such as native dynamic SQL, Java stored procedures, and system- and schema-level DBA triggers.
