transaction processing system (tps). overview: definition of transaction processing system. purposes...
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Transaction Processing System (TPS)
Definition of Transaction Processing System.Purposes TPS structure TPS functions TPS ControlsTPS components Features and characteristics Transactions Processing QualifiersTPS types some examples TPS Activities TPS advantages & disadvantages
introductionThe purpose of this document is to focus on the issues and concepts involved in transaction Processing System. A Transaction Processing System monitors transaction programs, a special kind of programs . The essence of a transaction program is that it manages data that must be left in a consistent state. Atransaction Processing System or Transaction Processing Monitor is a set of information which process the data transaction in database system that monitors transaction programs (a special kind of program).
Definition:The main information systems used for operational support in a business are transaction processing systems. This type of system processes data about transactions, which are events that have occurred that affect the business, such as the sale or purchase of goods.
A transaction processing system has 3 main purposes: keep records about the state of an organization, process transactions that affect these records, and produce outputs that report on transactions that have occurred. Transaction processing systems exist in all areas of an organization, and in all types of organizations. TPSs can be used by employees (order entry) or customers (bank ATMs). They can use various types of hardware, software, and networks. TPSs use stored data in both files and databases, and many types of programs.
The structure of a TPS generally consists of a user or other TPS that interacts with TPS software, and stored data used by the TPS. Users of the system are typically personnel who work with business transactions, such as salespeople. Input data comes from users and other TPS. Output includes data back to other TPSs, screens, and reports.
Like other information systems, TPSs perform four main functions: input, processing, output, and data storage. The input function accepts data for processing from outside the system. The processing output transforms the data in some way. The output function makes the processing results available outside the system. The storage function stores the data for use.Before transaction data can be brought into a TPS, it must be acquired from its source.
TPSs must have procedures to ensure the completeness of the data processing, and to minimize the chance of errors. In general, these procedures are called controls. Many types of controls are used, including :control totals, audit trails, and backup and recovery procedures.All data in a TPS may not be processed for various reasons, including hardware and software failures, and human error. One way that a TPS checks that all data is processed is through control totals. A control total is a number that is computed when data enters a system, and again after the system has processed the data.
Transaction processing systems provide three functional areas:
System runtime functions Transaction processing systems provide an execution environment that ensures the integrity, availability, and security of data. It also ensures fast response time and high transaction throughput. System administration functions Transaction processing systems provide administrative support that lets users configure, monitor, and manage their transaction systems. Application development functions Transaction processing systems provide functions for use in custom business applications, including functions to access data, to perform intercomputer communications, and to design and manage the user interface.
Components of a TPSUsers: The users are people employees of the company who own the TPS. They will use it to provide information about the system but will not enter data themselves. The informationthey provide from the TPSmay be used to provide inputs for other information systems.Participants: Participants are direct users of the system. These are the people who will enter the data. They include data entry operators, customer service operators, people working at checkouts and anyone carrying out the tasks required to process the data. People From The Environment: These are people who do not directly work for the company but people off the street who sometimes require the services of a TPS as they enter transactions and validate data.
Features and characteristics Rapid Processing The rapid processing of transactions is vital to the success of any enterprise now more than ever, in the face of advancing technology and customer demand for immediate action. TPS systems are designed to process transactions virtually instantly to ensure that customer data is available to the processes that require it. Reliability Similarly, customers will not tolerate mistakes. TPS systems must be designed to ensure that not only do transactions never slip past the net, but that the systems themselves remain operational permanently. TPS systems are therefore designed to incorporate comprehensive safeguards and disaster recovery systems. These measures keep the failure rate well within tolerance levels.
Features and characteristics (cont.):Standardisation Transactions must be processed in the same way each time to maximise efficiency. To ensure this, TPS interfaces are designed to acquire identical data for each transaction, regardless of the customer. Controlled Access Since TPS systems can be such a powerful business tool, access must be restricted to only those employees who require their use. Restricted access to the system ensures that employees who lack the skills and ability to control it cannot influence the transaction process.
Transactions Processing Qualifiers Atomicity Atomicity means that a transaction is either completed in full or not at all. For example, if funds are transferred from one account to another, this only counts as fide transaction if both the withdrawal and deposit take place. If one account is debited and the other is not credited, it does not qualify as a transaction. TPS systems ensure that transactions take place in their entirety. Consistency TPS systems exist within a set of operating rules (or integrity constraints). If an integrity constraint states that all transactions in a database must have a positive value, any transaction with a negative value would be refused.
Transactions Processing Qualifiers (cont.):Isolation Transactions must appear to take place in isolation. For example, when a fund transfer is made between two accounts the debiting of one and the crediting of another must appear to take place simultaneously. The funds cannot be credited to an account before they are debited from another. Durability Once transactions are completed they cannot be undone. To ensure that this is the case even if the TPS suffers failure, a log will be created to document all completed transactions.
Types of Transactions :Batch Processing Batch processing is a resource-saving transaction type that stores data for processing at pre-defined times. Batch processing is useful for enterprises that need to process large amounts of data using limited resources. Examples of batch processing include credit card transactions, for which the transactions are processed monthly rather than in real time. Credit card transactions need only be processed once a month in order to produce a statement for the customer, so batch processing saves IT resources from having to process each transaction individually.
Types of Transactions (cont.) :Real Time Processing In many circumstances the primary factor is speed. For example, when a bank customer withdraws a sum of money from his or her account it is vital that the transaction be processed and the account balance updated as soon as possible, allowing both the bank and customer to keep track of funds.
Batch Processing Vs Real Time Processing:Each transaction in real-time processing is unique. It is not part of a group of transactions, even though those transactions are processed in the same manner.Transactions in real-time processing are stand-alone both in the entry to the system and also in the handling of output. Real-time processing requires the master file to be available more often for updating and reference than batch processing. The database is not accessible all of the time for batch processing.
Batch Processing Vs Real Time Processing (cont):Real-time processing has fewer errors than batch processing, as transaction data is validated and entered immediately. With batch processing, the data is organized and stored before the master file is updated. Errors can occur during these steps. Infrequent errors may occur in real-time processing; however, they are often tolerated. It is not practical to shut down the system for infrequent errors. More computer operators are required in real-time processing, as the operations are not centralied. It is more difficult to maintain a real-time processing system than a batch processing system.
Transaction Processing Activities : Data collection: Capturing data necessary for the transactionData auditing: Check validity and completenessData correction: Correct the wrong dataData manipulation: Calculate, summarize Data storage: Update transactionsDocument production and reports: Create end results (paychecks)
The advantage is that usually transaction processing is really fast, it takes up usually a few seconds, however, if there a