Online analytical processing, or OLAP, is an approach to answer multi-dimensional analytical (MDA) queries swiftly in computing. OLAP is part of the broader category of business intelligence, which also encompasses relational databases, report writing and data mining. Typical applications of OLAP include business reporting for sales, marketing, management reporting, business process management (BPM), budgeting and forecasting, financial reporting and similar areas, with new applications emerging, such as agriculture.
Query languages, data query languages or database query languages (DQLs) are computer languages used to make queries in databases and information systems. A well known example is the Structured Query Language (SQL).
Holos is an influential OLAP product of the 1990s. Developed by Holistic Systems in 1987, the product remained in use until around 2004.
Essbase is a multidimensional database management system (MDBMS) that provides a multidimensional database platform upon which to build analytic applications. Essbase began as a product of Arbor Software, which merged with Hyperion Software in 1998. Oracle Corporation acquired Hyperion Solutions Corporation in 2007, as of 2009 Oracle marketed Essbase as "Oracle Essbase" and more recently, Essbase is offered as part of the Oracle Analytics Cloud. Until late 2005 IBM also marketed an OEM version of Essbase as DB2 OLAP Server.
In computer programming contexts, a data cube is a multi-dimensional ("n-D") array of values. Typically, the term datacube is applied in contexts where these arrays are massively larger than the hosting computer's main memory; examples include multi-terabyte/petabyte data warehouses and time series of image data.
Multidimensional Expressions (MDX) is a query language for online analytical processing (OLAP) using a database management system. Much like SQL, it is a query language for OLAP cubes. It is also a calculation language, with syntax similar to spreadsheet formulas.
Microsoft SQL Server Analysis Services, SSAS, is an online analytical processing (OLAP) and data mining tool in Microsoft SQL Server. SSAS is used as a tool by organizations to analyze and make sense of information possibly spread out across multiple databases, or in disparate tables or files. Microsoft has included a number of services in SQL Server related to business intelligence and data warehousing. These services include Integration Services, Reporting Services and Analysis Services. Analysis Services includes a group of OLAP and data mining capabilities and comes in two flavors - Multidimensional and Tabular.
Data Mining Extensions (DMX) is a query language for data mining models supported by Microsoft's SQL Server Analysis Services product.
OLE DB for OLAP is a Microsoft published specification and an industry standard for multi-dimensional data processing. ODBO is the standard application programming interface (API) for exchanging metadata and data between an OLAP server and a client on a Windows platform. ODBO extends the ability of OLE DB to access multi-dimensional (OLAP) data stores.
The following tables compare general and technical information for a number of online analytical processing (OLAP) servers. Please see the individual products articles for further information.
CubePort is a commercial software application that converts from Oracle Essbase to the analogous Microsoft product Microsoft Analysis Services, which is built into Microsoft SQL Server. This application achieves this through various analogy mapping techniques, and is a standard client-server application that runs on a Windows computer but may connect to non-Windows servers. CubePort converts the various OLAP structures and syntaxes in the source through an extraction process, interprets, and recreates in the target. The objective is to simulate exactly the behavior of the original source system to the target system.
Power Pivot is a feature of Microsoft Excel. It is available as an add-in in Excel 2010, 2013 in separate downloads, and as an add-in included with the Excel 2016 program. Power Pivot extends a local instance of Microsoft Analysis Services Tabular that is embedded directly into an Excel Workbook. This allows a user to build a ROLAP model in Power Pivot, and use pivot tables to explore the model once it is built. This allows Excel to act as a Self-Service BI platform, implementing professional expression languages to query the model and calculate advanced measures.
SQLstream is a distributed, SQL standards-compliant plus Java stream processing platform. SQLstream, Inc. is based in San Francisco, California and was launched in 2009 by Damian Black, Edan Kabatchnik and Julian Hyde, author of the open source Mondrian Relational OLAP Server Engine.
In computer science, in-memory processing is an emerging technology for processing of data stored in an in-memory database. Older systems have been based on disk storage and relational databases using SQL query language, but these are increasingly regarded as inadequate to meet business intelligence (BI) needs. Because stored data is accessed much more quickly when it is placed in random-access memory (RAM) or flash memory, in-memory processing allows data to be analysed in real time, enabling faster reporting and decision-making in business.
The following is provided as an overview of and topical guide to databases:
Array database management systems provide database services specifically for arrays, that is: homogeneous collections of data items, sitting on a regular grid of one, two, or more dimensions. Often arrays are used to represent sensor, simulation, image, or statistics data. Such arrays tend to be Big Data, with single objects frequently ranging into Terabyte and soon Petabyte sizes; for example, today's earth and space observation archives typically grow by Terabytes a day. Array databases aim at offering flexible, scalable storage and retrieval on this information category.
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. It is, in part, an evolution of the Multidimensional Expression (MDX) language developed by Microsoft for Analysis Services multidimensional models combined with Excel formula functions. It is designed to be simple and easy to learn, while exposing the power and flexibility of PowerPivot and SSAS tabular models.
icCube is a company founded in Switzerland that provides business intelligence software of the same name. The software can be fully embedded, can be hosted in a managed environment or installed locally, on premises.
Cubes is a light-weight open source multidimensional modelling and OLAP toolkit for development reporting applications and browsing of aggregated data written in Python programming language released under the MIT License.
ClickHouse is an open-source column-oriented DBMS for online analytical processing (OLAP).
