by n.gopinath ap/cse. two common multi-dimensional schemas are 1. star schema: consists of a fact...
TRANSCRIPT
![Page 1: By N.Gopinath AP/CSE. Two common multi-dimensional schemas are 1. Star schema: Consists of a fact table with a single table for each dimension 2. Snowflake](https://reader035.vdocuments.us/reader035/viewer/2022062715/56649d775503460f94a5857a/html5/thumbnails/1.jpg)
ByN.Gopinath
AP/CSE
![Page 2: By N.Gopinath AP/CSE. Two common multi-dimensional schemas are 1. Star schema: Consists of a fact table with a single table for each dimension 2. Snowflake](https://reader035.vdocuments.us/reader035/viewer/2022062715/56649d775503460f94a5857a/html5/thumbnails/2.jpg)
• Two common multi-dimensional schemas are
1. Star schema:• Consists of a fact table with a single
table for each dimension2. Snowflake Schema:• It is a variation of star schema, in which
the dimensional tables from a star schema are organized into a hierarchy by normalizing them.
![Page 3: By N.Gopinath AP/CSE. Two common multi-dimensional schemas are 1. Star schema: Consists of a fact table with a single table for each dimension 2. Snowflake](https://reader035.vdocuments.us/reader035/viewer/2022062715/56649d775503460f94a5857a/html5/thumbnails/3.jpg)
![Page 4: By N.Gopinath AP/CSE. Two common multi-dimensional schemas are 1. Star schema: Consists of a fact table with a single table for each dimension 2. Snowflake](https://reader035.vdocuments.us/reader035/viewer/2022062715/56649d775503460f94a5857a/html5/thumbnails/4.jpg)
![Page 5: By N.Gopinath AP/CSE. Two common multi-dimensional schemas are 1. Star schema: Consists of a fact table with a single table for each dimension 2. Snowflake](https://reader035.vdocuments.us/reader035/viewer/2022062715/56649d775503460f94a5857a/html5/thumbnails/5.jpg)
Fact constellation is a set of tables that share some dimension tables. However, fact constellations limit the possible queries for the warehouse.
![Page 6: By N.Gopinath AP/CSE. Two common multi-dimensional schemas are 1. Star schema: Consists of a fact table with a single table for each dimension 2. Snowflake](https://reader035.vdocuments.us/reader035/viewer/2022062715/56649d775503460f94a5857a/html5/thumbnails/6.jpg)
Data warehouse also utilizes indexing to support high performance access.
A technique called bitmap indexing constructs a bit vector for each value in domain being indexed.
Indexing works very well for domains of low cardinality.
![Page 7: By N.Gopinath AP/CSE. Two common multi-dimensional schemas are 1. Star schema: Consists of a fact table with a single table for each dimension 2. Snowflake](https://reader035.vdocuments.us/reader035/viewer/2022062715/56649d775503460f94a5857a/html5/thumbnails/7.jpg)
Thank you…