sql ch9

beta release

In the subsequent release (the so called beta release) the data warehousing system is deployed to a selected group of users to test the usability of the system.

Load

Load refers to the process of loading the extracted, transformed, and quality assured data into the target data warehouse. the initial load is the first load. every load after is a refresh load.

Extraction

Extraction refers to the retrieval of analytically useful data sources that will eventually be loaded into the data warehouse.

Online anayltical process (OLAP)

refers to querying and presenting data from data warehouses and or data marts for analytical purposes. OLAP is read only and exclusively for retrieval of data from analytical repositories to be used in decision making. OLAP tools are also known as business intelligence (BI) tools. or OLAP/BI tools.

Online transaction processing (OLTP)

refers to updating (inserting, modifying, and deleting), querying, and presenting data from databases for operational purposes. day to day purposes

Transformation

Transformation refers to the process of transforming the structure of extracted data in order to fit the structure to the target data warehouse model.

ETL

A set of processes is used to populate the data warehouse tables with appropiate relevant data retrieved from operational databases. This set of process is known as ETL (extraction, transformation, and load).

Relational Online analytical processing (ROLAP)

Rolap architecture i poses no limitations on the size of the database or on the kind of analysis but is slower than Molap.

Production Release

The actual deployment of a functioning data warehousing system is also known as production release.

alpha release

a data warwhouse and the associated front end applications are deployed internally to the members of the development team for intial testing of its functionalities.

Multidimensional online analytical processing (MOLAP)

in the MOLAP the data from the warehouse or from the operational sources is stored in multidimensional cubes.

activate data warehouses

the loads occur in micro batches that happen continuously, ensuring that data in the data warehouse is updated close to real time (enabling analysis of the latest data).

data cleansing (scrubbing)

the process of transformation has to enable the detection and correction of the low qaulity data.

Drill down

the purpose is to make the granuality finer. does not delete data

Slice and dice

the slice and dice operation adds, replaces, or eliminates specified dimension attributes (or particular values of dimension attributes) from the already displayed result. slice is 1 dice is 2 or more

Drill up

to make the data coarser. does not add data

pivot (table)

unlike the slice and dice operation, the pivot (rotate) operation does not change the values displayed in the original query, it just reorganizes them.

Hybrid online analytical processing (HOLAP)

Holap combines the strengths both molap and rolap. the relational database can be used to store the detailed transaction level data and the multidimensional cube can be used to store summary data.

multidimensional database model

an alternative for implementation of dimensionally modeled data is via the multidimensional database model. in this model, a database is a collection of so called cubes.

executive dashboard

is intended for use by higher level decision makers within an organization.