An aggregate is a type of summary used in dimensional models of data warehouses to shorten the time it takes to provide answers to typical queries on large sets of data . The reason why aggregates can make such a dramatic increase in the performance of a data warehouse is the reduction of the number of rows to be accessed when responding to a query.
19-572: (Redirected from Aggregates ) [REDACTED] Look up aggregate in Wiktionary, the free dictionary. Aggregate or aggregates may refer to: Computing and mathematics [ edit ] Aggregate (data warehouse) , a part of the dimensional model that is used to speed up query time by summarizing tables Aggregate analysis, a technique used in amortized analysis in computer science, especially in analysis of algorithms Aggregate class ,
38-419: A building material . In pedology , an aggregate is a mass of soil particles. If the aggregate has formed naturally, it can be called a ped ; if formed artificially, it can be called a clod. Aggregates are used extensively in the construction industry Often in making concrete , a construction aggregate is used, with about 6 billion tons of concrete produced per year. This mineralogy article
57-577: A concept in the Domain-driven Design software development process Aggregate Server Access Protocol , used by the Reliable server pooling (RSerPool) framework Aggregate throughput , total throughput measured over all links and in all directions in a communication network Economics [ edit ] Aggregate demand , the total demand for final goods and services during a specific time period in an economy Aggregate income ,
76-407: A lot of overhead to build all possible aggregations, it is a good idea to choose a subset of tables on which to make aggregations. The best way to choose this subset and decide which aggregations to build is to monitor queries and design aggregations to match query patterns. Having aggregate data in the dimensional model makes the environment more complex. To make this extra complexity transparent to
95-570: A mass of crystals, rock particles, or soil particles Aggregate (rocket family) , in rocketry, a set of experimental rocket designs developed in Nazi Germany Arts, entertainment, and media [ edit ] Aggregate, in music, is a set of all twelve pitch classes, also known as the total chromatic The Aggregate , a 1988 album by Anthony Braxton and the Rova saxophone Quartet Other uses [ edit ] Aggregate, in
114-413: A rolled up dimension. Rolled up dimensions should be shrunken versions of the dimensions associated with the granular base facts. This way, the aggregated dimension tables should conform to the base dimension tables. In 1996, Ralph Kimball , who is widely regarded as one of the original architects of data warehousing, stated: The single most dramatic way to affect performance in a large data warehouse
133-517: A specific time period in an economy Religion [ edit ] Aggregate (Sanskrit, skandha ; PΔli, khandha), in Buddhism, a category of sensory experiences Aggregates , in some Christian churches, are combinations of groupings of multiples of canonical hours (i.e., offices) that form a single religious service Science [ edit ] Biology [ edit ] Aggregate fruit , in botanical terminology, fruit that develops from
152-443: A type of class supported by C++ Aggregate data , in statistics, data combined from several measurements Aggregate function , aggregation function, in database management is a function wherein the values of multiple rows are grouped together to form a single summary value Aggregate Level Simulation Protocol (ALSP), a protocol and supporting software that enables simulations to interoperate with one another Aggregate root ,
171-449: Is different from Wikidata All article disambiguation pages All disambiguation pages Aggregate (data warehouse) In its simplest form, an aggregate is a simple summary table that can be derived by performing a Group by SQL query. A more common use of aggregates is to take a dimension and change its granularity. When changing the granularity of the dimension the fact table has to be partially summarized to fit
190-427: Is to provide a proper set of aggregate (summary) records that coexist with the primary base records. Aggregates can have a very significant effect on performance, in some cases speeding queries by a factor of one hundred or even one thousand. No other means exist to harvest such spectacular gains. Having aggregates and atomic data increases the complexity of the dimensional model. This complexity should be transparent to
209-487: The benefits in the latter case is restricted to a single front end BI tool Aggregate (geology) In the Earth sciences , aggregate has three possible meanings. In mineralogy and petrology , an aggregate is a mass of mineral crystals, mineraloid particles or rock particles. Examples are dolomite , which is an aggregate of crystals of the mineral dolomite , and rock gypsum , an aggregate of crystals of
SECTION 10
#1732772076654228-579: The merging of ovaries originating from a single flower Aggregate species (Wiktionary) or species aggregate, a named species representing a range of very closely related organisms; see also species complex Materials science [ edit ] Aggregate (composite) , in materials science, a component of a composite material that resists compressive stress Construction aggregate , materials used in construction, including sand, gravel, crushed stone, slag, or recycled crushed concrete Other uses in science [ edit ] Aggregate (geology) ,
247-421: The mineral gypsum . Lapis lazuli is a type of rock composed of an aggregate of crystals of many minerals including lazurite , pyrite , phlogopite , calcite , potassium feldspar , wollastonite and some sodalite group minerals. In the construction industry, an aggregate (often referred to as a construction aggregate ) is sand , gravel or crushed rock that has been mined or quarried for use as
266-412: The new grain of the new dimension , thus creating new dimensional and fact tables, to fit this new level of grain. Aggregates are sometimes referred to as pre-calculated summary data, since aggregations are usually precomputed, partially summarized data, that are stored in new aggregated tables. When facts are aggregated, it is either done by eliminating dimensionality or by associating the facts with
285-415: The same term [REDACTED] This disambiguation page lists articles associated with the title Aggregate . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Aggregate&oldid=1237982094 " Category : Disambiguation pages Hidden categories: Short description
304-412: The social sciences, a gathering of people into a cluster or a crowd that does not form a true social group Aggregate Industries , a manufacturer of aggregate materials Aggregate score , in sport, is the sum of two scorelines in a two-legged match See also [ edit ] Aggregates, West Virginia Aggregation (disambiguation) Aggregator (disambiguation) Topics referred to by
323-446: The total of all incomes in an economy without adjustments for inflation, taxation, or types of double counting Aggregate expenditure , a measure of national income Aggregate Spend (US), a process to monitor the total amount spent by healthcare manufacturers on individual healthcare professionals and organizations through payments and gifts of various kinds Aggregate supply , the total supply of goods and services produced during
342-418: The user, functionality known as aggregate navigation is used to query the dimensional and fact tables with the correct grain level. The aggregate navigation essentially examines the query to see if it can be answered using a smaller, aggregate table. Implementations of aggregate navigators can be found in a range of technologies: It is generally recommended to use either of the first three technologies, since
361-436: The users of the data warehouse, thus when a request is made, the data warehouse should return data from the table with the correct grain. So when requests to the data warehouse are made, aggregate navigator functionality should be implemented, to help determine the correct table with the correct grain. The number of possible aggregations is determined by every possible combination of dimension granularities. Since it would produce
#653346