Basic concepts of PL/SQL

PL/SQL indicates the SQLProcedural Language extension(Procedural Language extension to SQL ). By adding the programming structure and sub-Program, PL/SQL to expand SQL.

Realize that PL/SQL is not independentProgramming LanguageIs very important. PL/SQL is a part of Oracle RDBMS and can reside in two environments-client and server.

In both environments, any PL/SQL block or subroutine is processed by the PL/SQL engine. It is a special component of many Oracle products. The PL/SQL engine processes and executes any PL/SQL statements, and sends the statements to the SQL statement processor. The SQL statement processor is usually located on the Oracle server. Demonstrate the PL/SQL engine residing on the Oracle server:

When the PL/SQL engine is on the client, it processes PL/SQL on the client just like Oracle Developer Tools. All SQL statements nested in PL/SQL statement blocks are sent to the Oracle server for further processing. When PL/SQL statement blocks do not include any SQL statements, the entire statement block is executed on the client.