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New Technology and the DBA

The DBA is at the center of the action whenever new ways of doing business and new technologies are introduced to the organization. Data is the lifeblood of modern business, data is housed by the database, and the DBA is the expert who understands database technology—and in particular, how databases can be integrated with other new technologies.

Let's examine three specific newer technologies that rely on database administration—at least somewhat—to be effectively implemented: database-coupled application logic, Internet-enabled e-business development, and handheld computing.

Procedural DBAs: Managing Database Logic
Until recently, the purpose of a database management system was, appropriately enough, to store, manage, and access data. Although these core capabilities are still required of modern DBMS products, additional procedural functionality is slowly becoming not just a nice feature to have, but a necessity. Features such as triggers, user-defined functions, and stored procedures provide the ability to define business rules to the DBMS instead of in separate application programs. These features couple application logic tightly to the database server.

Since all of the most popular RDBMS products provide sometimes-complex features to facilitate database-coupled procedural logic, additional management discipline is required to ensure the optimal use of these features. Typically, as new features are added, their administration, design, and management are assigned to the DBA by default. However, without proper planning and preparation, chaos can ensue. First let's examine how database logic is stored in a DBMS.

Stored Procedures
Stored procedures can be thought of as programs that live in a database. The procedural logic of a stored procedure is maintained, administered, and executed through the database commands. The primary reason for using stored procedures is to move application code from a client workstation to the database server. Stored procedures typically consume less overhead in a client/server environment because one client can invoke a stored procedure that causes multiple SQL statements to be run. The alternative, the client executing multiple SQL statements directly, increases network traffic and can degrade overall application performance.

A stored procedure is a freestanding database object; it is not "physically" associated with any other object in the database. A stored procedure can access and/or modify data in many tables.

Triggers
Triggers are event-driven specialized procedures that are attached to database tables. The trigger code is automatically executed by the RDBMS as data changes in the database. Each trigger is attached to a single, specified table. Triggers can be thought of as an advanced form of rule or constraint that uses procedural logic. A trigger cannot be directly called or executed; it is automatically executed (or "fired") by the RDBMS as the result of a SQL INSERT, UPDATE, or DELETE statement issued on its associated table. Once a trigger is created, it is always executed when its firing event occurs.

User-Defined Functions
A user-defined function (UDF) provides a result based on a set of input values. UDFs are programs that can be executed in place of standard, built-in SQL scalar or column functions. A scalar function transforms data for each row of a result set; a column function evaluates each value for a particular column in each row of the results set and returns a single value. Once written, and defined to the RDBMS, a UDF becomes available just like any other built-in database function.

Administering Stored Procedures, Triggers, and UDFs
Once developers begin to rely on stored procedures, triggers, and UDFs, DBAs need to take steps to manage them properly. DBAs must grapple with the issues of quality, maintainability, efficiency, and availability. How and when will these procedural objects be tested? The impact of a failure is enterprisewide, increasing the visibility and criticality of these objects. Who is responsible if they fail? The answer must be—the DBA.

The role of administering procedural database logic should fall upon someone skilled in that discipline. A new type of DBA is required to accommodate the administration of database procedural logic. This new role can be defined as a procedural DBA.

The procedural DBA is responsible for those database management activities that require procedural logic support. He ensures that stored procedures, triggers, and user-defined functions are effectively planned, implemented, shared, and reused. The procedural DBA also takes primary responsibility for coding and testing all triggers. Stored procedures and user-defined functions, although likely to be coded by application programmers, should be reviewed for accuracy and performance by procedural DBAs.

The Internet: From DBA to e-DBA
Companies of every size are using Internet technologies to speed up business processes. Indeed, e-business has evolved as a new term to describe the transformation of key business processes using Internet technologies. Modern organizations use the Web to communicate with their partners and customers, to connect with their back-end databases, and to conduct transactions (e-commerce). E-business is the integration of traditional information technology with the Internet. This integration creates a more nimble business, prepared for the trials and tribulations of conducting business in the 21st century.

The PDA DBA
Personal digital assistant devices, better known as PDAs, are fast becoming a necessity for modern executives and businessmen. A PDA is a handheld computing device. Whether your PDA of choice is a Palm Pilot or a PocketPC, your PDA may soon have a DBMS running on it. Why is that interesting? Does it change the way you will use your PDA? What will that mean to your IT department?

PDAs offer many benefits. The devices are small and therefore easily transportable. They enhance a mobile worker's ability to be mobile. However, challenges must be faced as organizations incorporate PDAs into their infrastructure. Companies with remote workers such as a distributed sales force or delivery tracking services will most likely be the first impacted. The data on the PDAs must be managed professionally to ensure integrity and reliability. Because the device is remote, sharing of data can be difficult. The data on the PDAs must be reliably synchronized with existing enterprise systems and databases.

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