OLTP
- application oriented
- detailed
- accurate, as of the moment of access
- serves the clerical community
- can be updated
- requirements for processing understood before initial development
- compatible with the Software Development Life Cycle
- performance sensitive
- accessed a unit at a time
- transaction driven
- control of update a major concern in terms of ownership
- high availability
- managed in its entirety
- non redundancy
- static structure; variable contents
- small amount of data used in a process
OLAP
- subject oriented
- summarized, otherwise refined
- represents values over time, snapshots
- serves the managerial community
- is not updated
- requirements for processing not completely understood before development
- completely different life cycle
- performance relaxed
- accessed a set at a time
- analysis driven
- control of update no issue
- relaxed availability
- managed by subsets
- redundancy
- flexible structure
- large amount of data used in a process
OLTP
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OLAP
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Contains Current Information
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Contains previous + current
information
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Used to Run business
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Used to analyze business
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Data is updated and deleted
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Data are only read
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Size is less than 2TB
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Size is more than 2TB
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OLAP
has 4 types
- DOLAP (Desktop OLAP): Ex: FoxPro
- ROLAP (Relational OLAP): Ex: RDBMS (Tables)-BOXIR2, COGNOS (Analysis)
- MOLAP (Multi Dimensional): Ex: Cubes, BOXIR2, COGNOS (Tools)
- HOLAP (Hybrid OLAP): ROLAP+MOLAP.
Data Modeling: Designing database/tables.
There are
many types of data modeling but we use only 2 types.
- Entity relationship (E-R) Model: cannot allow to store duplicates values
- Dimensional Model: Allow Duplicate values.
Dimensional
modeling has 3 phases.
- Conceptual Modeling: We are analyzing number of tables and columns.
- Logical modeling: Once tables are created, we are going to relate tables.
- Physical modeling: We are moving all schema’s/tables to data warehouse
NOTE:
SCHEMA-
Collection of fact table and dimensional table.
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