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The impact of Big Data on making evidence-based decisions
Published in Matthias Dehmer, Frank Emmert-Streib, Frontiers in Data Science, 2017
Rodica Neamtu, Caitlin Kuhlman, Ramoza Ahsan, Elke Rundensteiner
The data warehouse solution involves the selection of a storage model and must address the challenge of the first V of Big Data—volume. Traditional data warehousing uses a relational database management system [2–4], which are designed and managed using Structured Query Language (SQL). In such systems, data are organized in relations, or tables, according to a logical model such as a star schema structure [20], which is composed of one central fact table and numerous dimension tables that radiate out from it [21]. Primary values are recorded in the fact table, and descriptive metadata are stored in separate dimension tables. This design is a tried-and-true solution for traditional databases. However, it relies on one centralized storage solution managed in-house and is somewhat rigid in the organizational structure it allows.
Data Mining
Published in Bogdan M. Wilamowski, J. David Irwin, Intelligent Systems, 2018
A star schema is composed of the fact (central) table with keys to (four) dimension tables (redundancies are possible). A snowflake schema is composed of centralized fact tables connected to dimensions, hence resembling a snowflake (E-R relationship). The snowflake schema is easier to maintain, less effective in browsing (some dimension tables are normalized, no redundancies). A collection of stars produces fact constellation (two fact tables) schema (dimension tables are now shared among fact tables).
Optimizing Join in HIVE Star Schema Using Key/Facts Indexing
Published in IETE Technical Review, 2018
Hussien SH. Abdel Azez, Mohamed H. Khafagy, Fatma A. Omara
Therefore, structured database star schema (Star Join Schema) is the simplest style of the data warehouse schema. This star schema has one or more fact tables referencing a large number of dimension tables. The star schema is more efficient for creating a simple query. In addition, it represents one of the complicated schemas that require almost joining schema tables to gather information for the decision-makers [5,6]. On the other hand, TPC-H is one of the massively used star schema decision-support benchmarks (see Figure 1) [7].