As large-scale RDBMS, Oracle is used most widely in enterprise application. PL/SQL is programming language based on SQL and expanded by Oracle. We could adopt PL/SQL to develop trigger, view, stored procedure, package and function to process data. In many architecture designs of enterprise application, stored procedure is utilized to achieve batch processing which does not need more user interaction, owns complex logic and often involves a large amount of data, making the database have dual roles which are data storage and business process. With the increasing amount of data, how to guarantee performance of stored procedure is very important. In this article, based on successful practice of performance tuning to oversea version of China Aviation International Passenger Revenue Accounting Solution, the author introduces Oracle's OEM and AWR report simply which are used to discover performance problem, and three technologies as optimization strategy adopted in batch processing application based on PL/SQL are summarized, they are code refactoring to decrease I/O, temporary table and simulating multi-thread. The target of this article is to provide thinking for developer and maintainer engaging in continuous optimization about the application utilizing such architecture.