#JAVA 7 DOWNLOAD PL CODE#
Applications written in database APIs can invoke PL/SQL stored subprograms and send PL/SQL code blocks to the database for execution. PL/SQL is integrated with the database, supporting all Oracle SQL statements, functions, and data types. PL/SQL is the Oracle Database procedural extension to SQL. You can use the following languages to store data logic in Oracle Database: Because subprogram calls are quick and efficient, a single call can start a compute-intensive stored subprogram, reducing network traffic. Also, subprograms increase scalability by centralizing application processing on the server, enabling clients to reuse code. The database and not the application determines the best way to perform tasks on a given operating system. The principal benefit of server-side programming is that functionality built into the database can be deployed anywhere. This chapter explains the second approach. You can also create a trigger, which is named program unit that is stored in the database and invoked in response to a specified event. Use server-side programming to develop data logic that resides in the databaseĪn application can explicitly invoke stored subprograms (procedures and functions), written in PL/SQL (pronounced P L sequel) or Java. Alternatively, you can eliminate the precompilation step and use an API such as Java Database Connectivity (JDBC) or Oracle Call Interface (OCI) to enable the application to interact with the database.
You can place SQL statements in source code and submit it to a precompiler or Java translator before compilation. Use client-side programming to embed SQL statements in applications written in procedural languages such as C, C++, or Java The basic development approaches are as follows: The problem is how procedural database applications requiring conditional logic and program flow control can use SQL.
#JAVA 7 DOWNLOAD PL UPDATE#
If a raise is called for, then the application must adjust the salary and email the manager otherwise, the application must update a report. A necessary condition of a raise is that the employee did not receive more than three raises in the last five years. However, suppose you want an application to determine whether each employee in the data set deserves a raise based on salary and department performance. The preceding statement requests data, but does not apply logic to the data. SELECT employee_id, department_id, last_name, salary FROM employees In a procedural language program, most statement execution depends on previous or subsequent statements and on control structures, such as loops or conditional branches, that are not available in SQL.įor an illustration of the difference between procedural and nonprocedural languages, suppose that the following SQL statement queries the employees table: In a nonprocedural language such as SQL, the set of data to be operated on is specified, but not the operations to be performed or the manner in which they are to be carried out.
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