enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Group by (SQL) - Wikipedia

    en.wikipedia.org/wiki/Group_by_(SQL)

    A GROUP BY statement in SQL specifies that a SQL SELECT statement partitions result rows into groups, based on their values in one or several columns. Typically, grouping is used to apply some sort of aggregate function for each group. [1] [2] The result of a query using a GROUP BY statement contains one row for

  3. Summation by parts - Wikipedia

    en.wikipedia.org/wiki/Summation_by_parts

    The formula for an integration by parts is () ′ = [() ()] ′ ().. Beside the boundary conditions, we notice that the first integral contains two multiplied functions, one which is integrated in the final integral (′ becomes ) and one which is differentiated (becomes ′).

  4. Online analytical processing - Wikipedia

    en.wikipedia.org/wiki/Online_analytical_processing

    In computing, online analytical processing, or OLAP (/ ˈ oʊ l æ p /), is an approach to quickly answer multi-dimensional analytical (MDA) queries. [1] The term OLAP was created as a slight modification of the traditional database term online transaction processing (OLTP). [2]

  5. Apache Spark - Wikipedia

    en.wikipedia.org/wiki/Apache_Spark

    Spark Core is the foundation of the overall project. It provides distributed task dispatching, scheduling, and basic I/O functionalities, exposed through an application programming interface (for Java, Python, Scala, .NET [16] and R) centered on the RDD abstraction (the Java API is available for other JVM languages, but is also usable for some other non-JVM languages that can connect to the ...

  6. Function (computer programming) - Wikipedia

    en.wikipedia.org/wiki/Function_(computer...

    In computer programming, a function (also procedure, method, subroutine, routine, or subprogram) is a callable unit [1] of software logic that has a well-defined interface and behavior and can be invoked multiple times.

  7. Subset sum problem - Wikipedia

    en.wikipedia.org/wiki/Subset_sum_problem

    The subset sum problem (SSP) is a decision problem in computer science. In its most general formulation, there is a multiset of integers and a target-sum , and the question is to decide whether any subset of the integers sum to precisely . [1] The problem is known to be NP-complete.

  8. Data transformation (statistics) - Wikipedia

    en.wikipedia.org/wiki/Data_transformation...

    This is called the rank transform, [14] and creates data with a perfect fit to a uniform distribution. This approach has a population analogue. Using the probability integral transform , if X is any random variable , and F is the cumulative distribution function of X , then as long as F is invertible, the random variable U = F ( X ) follows a ...

  9. Snowflake schema - Wikipedia

    en.wikipedia.org/wiki/Snowflake_schema

    The snowflake schema is a variation of the star schema, featuring normalization of dimension tables. In computing, a snowflake schema or snowflake model is a logical arrangement of tables in a multidimensional database such that the entity relationship diagram resembles a snowflake shape.