Seeder question: I have heard several references made to OLAP databases and OLTP databases - what do the terms mean, and what are the key differences?
asked
OLAP and OLTP databases
OLAP = Online Analytical Processing OLTP = Online Transaction Processing
In general, OLAP databases are read much more frequently than written, while OLTP databases experience frequent writes. Therefore, OLAP databases tend to be more denormalized with more indexes (optimized for reading). OLTP databases, on the other hand, are typically optimized for writing with many, smaller normalized tables and only the minimum number of required indexes.
The term OLAP is sometimes used specifically for star or snowflake schemas for Analysis Services and similar tools, but it can also refer to any data warehouse.
OLTP refers to the common type of workload or usage of a database in operational systems.
OLAP refers to a set of technologies often used in decision support systems.
Sometimes the two terms are used as if they complement each other but in my view a better complement of OLTP is DSS (Decision Support System). OLTP/DSS both describe the type of use the system is put to whereas OLAP describes what technology is being used.
dportas has hit on something here, the term OLAP is often used and abused.
Some of the other terms often mixed up in this are:
- DSS : Decision Support Systems
- EIS : Executive Information Systems
- MIS : Management Information Systems
- BI : Business Intelligence
all of which can be used to mean the same thing. Usually depending on whatever the trend is at the time. In the 80s, EIS was all the rage, then DSS became popular and today's buzzword is BI.
OLAP as a technology is sometimes interchanged with
- Cubes
- Multi-dimensional data
