Search results
Results from the WOW.Com Content Network
A database model is a type of data model that determines the logical structure of a database. It fundamentally determines in which manner data can be stored, organized and manipulated. The most popular example of a database model is the relational model , which uses a table-based format.
A database index is a data structure that improves the speed of data retrieval operations on a database table at the cost of additional writes and storage space to maintain the index data structure. Indexes are used to quickly locate data without having to search every row in a database table every time said table is accessed.
Update database and/or update model No Oracle SQL Developer Data Modeler Logical, physical Barker, IE (Crow’s foot), and Bachman Yes Yes Update database and/or update model Yes PowerDesigner: Conceptual, logical, physical IDEF1X, IE (Crow’s foot), and more Yes Yes Update database and/or update model Yes Software Ideas Modeler: Conceptual ...
Data models represent information areas of interest. While there are many ways to create data models, according to Len Silverston (1997) [7] only two modeling methodologies stand out, top-down and bottom-up: Bottom-up models or View Integration models are often the result of a reengineering effort. They usually start with existing data ...
Rather than two or three dimensions: row, column and sheet, the functional model supports as many dimensions as are necessary. Another advantage of the functional model is that it is a database with features such as data independence, concurrent multiuser access, integrity, scalability, security, audit trail, backup/recovery, and data integration.
Database normalization is the process of structuring a relational database in accordance with a series of so-called normal forms in order to reduce data redundancy and improve data integrity. It was first proposed by British computer scientist Edgar F. Codd as part of his relational model .
Data Analysis Expressions (DAX) is the native formula and query language for Microsoft PowerPivot, Power BI Desktop and SQL Server Analysis Services (SSAS) Tabular models. DAX includes some of the functions that are used in Excel formulas with additional functions that are designed to work with relational data and perform dynamic aggregation .
MarkLogic introduced bitemporal data support in version 8.0. Time stamps for Valid and System time are stored in JSON or XML documents. [2]XTDB [3] (formerly Crux) is an open source database that indexes documents using an EAV data model and provides point-in-time bitemporal SQL & Datalog queries.