Unit-2 MISDSSTPSOLAPOLTP

Transaction Processing Systems• As the name implies, Transaction Processing Systems

("TPS") are designed to process routine transactions efficiently and accurately. A business will have several TPS.

• for example:• - Billing systems to send invoices to customers

- Systems to calculate the weekly and monthly payroll and tax payments- Production and purchasing systems to calculate raw material requirements- Stock control systems to process all movements into, within and out of the business

Management Information System

• MIS is mainly concerned with internal sources of information.

• MIS usually take data from the transaction processing systems (see below) and summarise it into a series of management reports.

• MIS reports tend to be used by middle management and operational supervisors

Decision-support systems• DSS are specifically designed to help

management make decisions in situations where there is uncertainty about the possible outcomes of those decisions.

• DSS comprise tools and techniques to help gather relevant information and analyse the options and alternatives.

• DSS often involves use of complex spreadsheet and databases to create "what-if" models.

Executive Support System• An Executive Support System ("ESS") is designed to

help senior management make strategic decisions. It gathers, analyses and summarises the key internal and external information used in the business.

• A good way to think about an ESS is to imagine the senior management team in an aircraft cockpit - with the instrument panel showing them the status of all the key business activities.

• ESS typically involve lots of data analysis and modelling tools such as "what-if" analysis to help strategic decision-making.

OLAP• - OLAP (On-line Analytical Processing) is

characterized by relatively low volume of transactions. Queries are often very complex and involve aggregations.

• For OLAP systems a response time is an effectiveness measure.

• OLAP applications are widely used by Data Mining techniques.

• In OLAP database there is aggregated, historical data, stored in multi-dimensional schemas (usually star schema).

• OLAPs were designed to provide analysis and queries efficiently as compared to real time transaction processing in OLTP. As heavy management queries were transferred to OLAP, performance of OLTP system was not affected. OLAP uses multidimensional model, with the primary purpose of running complex analytical and ad-hoc queries.

OLTP• - OLTP (On-line Transaction Processing) is

characterized by a large number of short on-line transactions (INSERT, UPDATE, DELETE).

• The main emphasis for OLTP systems is put on very fast query processing, maintaining data integrity in multi-access environments and an effectiveness measured by number of transactions per second.

• In OLTP database there is detailed and current data, and schema used to store transactional databases is the entity model (usually 3NF).

OLTP

• OLTP system solved a critical business problem of automating daily business functions and running real time reports and analysis.

• But these systems were not designed for analysis and queries. Frustration started to build in Business management as OLTP systems could not provide the analysis on the data.

• Resource heavy management analytical queries started to affect performance of OLTP systems and users of OLTP system also got frustrated.

OLAP vs OLTP

• Source of Data - OLAP gathers data from multiple systems (including OLTP systems). OLTP records data. OLAP gets data periodically from backend systems (such as OLTP). OLTP is updated regularly as transactions are recorded.

• Purpose – Purpose of OLTP is to carry out day to day business functions. Purpose of OLAP is to support decision making and provide answers to business and management queries.

OLAP vs OLTP• Reporting – OLTP reports tend to run on low

volume of data and returns few records. OLAP queries typically run on huge volume of data.

• Resource requirements – OLAP requires huge space and CPU resources to store volume of data and run complex queries. OLTP requires relatively less system resources.

• Execution Speed – OLTP runs faster than OLAP as queries tends to be simple. However, for similar queries OLAP runs faster as OLAPs are designed to run complex queries.

OLTP System OLTP System Online Transaction Processing Online Transaction Processing (Operational System)(Operational System)

OLAP System OLAP System Online Analytical Processing Online Analytical Processing (Data Warehouse(Data Warehouse

Source of dataSource of data Operational data; OLTPs are the original Operational data; OLTPs are the original source of the data.source of the data.

Consolidation data; OLAP data comes Consolidation data; OLAP data comes from the various OLTP Databasesfrom the various OLTP Databases

Purpose of dataPurpose of data To control and run fundamental business To control and run fundamental business taskstasks

To help with planning, problem solving, To help with planning, problem solving, and decision supportand decision support

What the dataWhat the data Reveals a snapshot of ongoing Reveals a snapshot of ongoing business processes

Multi-dimensional views of various Multi-dimensional views of various kinds of business activitieskinds of business activities

Inserts and Inserts and UpdatesUpdates

Short and fast inserts and updates initiated by Short and fast inserts and updates initiated by end usersend users

Periodic long-running batch jobs Periodic long-running batch jobs refresh the datarefresh the data

QueriesQueries Relatively standardized and simple queries Relatively standardized and simple queries Returning relatively few recordsReturning relatively few records

Often complex queries involving Often complex queries involving aggregationsaggregations

Processing Processing SpeedSpeed

Typically very fastTypically very fast Depends on the amount of data Depends on the amount of data involved; batch data refreshes and involved; batch data refreshes and complex queries may take many hours; complex queries may take many hours; query speed can be improved by query speed can be improved by creating indexescreating indexes

Space Space RequirementsRequirements

Can be relatively small if historical data is Can be relatively small if historical data is archivedarchived

Larger due to the existence of Larger due to the existence of aggregation structures and history aggregation structures and history data; requires more indexes than OLTPdata; requires more indexes than OLTP

Data Base Data Base DesignDesign

Highly normalized with many tablesHighly normalized with many tables Typically de-normalized with fewer Typically de-normalized with fewer tables; use of star and/or snowflake tables; use of star and/or snowflake schemasschemas

Backup and Backup and RecoveryRecovery

Backup religiously; operational data is critical Backup religiously; operational data is critical to run the business, data loss is likely to entail to run the business, data loss is likely to entail significant monetary loss and legal liabilitysignificant monetary loss and legal liability

Instead of regular backups, some Instead of regular backups, some environments may consider simply environments may consider simply reloading the OLTP data as a recovery reloading the OLTP data as a recovery methodmethod

• MOVIE :- HOW TO DESIGN A SIMPLE REPORT THROUGH OLAP