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  2. File:Programmation SQL-fr.pdf - Wikipedia

    en.wikipedia.org/wiki/File:Programmation_SQL-fr.pdf

    You are free: to share – to copy, distribute and transmit the work; to remix – to adapt the work; Under the following conditions: attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made.

  3. Query optimization - Wikipedia

    en.wikipedia.org/wiki/Query_optimization

    The search space can become quite large depending on the complexity of the SQL query. There are two types of optimization. These consist of logical optimization—which generates a sequence of relational algebra to solve the query—and physical optimization—which is used to determine the means of carrying out each operation.

  4. Hierarchical and recursive queries in SQL - Wikipedia

    en.wikipedia.org/wiki/Hierarchical_and_recursive...

    In SQL:1999 a recursive (CTE) query may appear anywhere a query is allowed. It's possible, for example, to name the result using CREATE [ RECURSIVE ] VIEW . [ 16 ] Using a CTE inside an INSERT INTO , one can populate a table with data generated from a recursive query; random data generation is possible using this technique without using any ...

  5. Database normalization - Wikipedia

    en.wikipedia.org/wiki/Database_normalization

    Download as PDF; Printable version; ... as the problems they exist to solve rarely appear in practice. ... such as Microsoft SQL Server 2012 and later, let you ...

  6. Halloween Problem - Wikipedia

    en.wikipedia.org/wiki/Halloween_Problem

    In computing, the Halloween Problem refers to a phenomenon in databases in which an update operation causes a change in the physical location of a row, potentially allowing the row to be visited again later in the same update operation. This could even cause an infinite loop in some cases where updates continually place the updated record ahead ...

  7. Skyline operator - Wikipedia

    en.wikipedia.org/wiki/Skyline_operator

    The skyline operator is the subject of an optimization problem and computes the Pareto optimum on tuples with multiple dimensions.. This operator is an extension to SQL proposed by Börzsönyi et al. [1] to filter results from a database to keep only those objects that are not worse in multiple dimensions than any other.

  8. Object–relational impedance mismatch - Wikipedia

    en.wikipedia.org/wiki/Object–relational...

    Object–relational impedance mismatch is a set of difficulties going between data in relational data stores and data in domain-driven object models. Relational Database Management Systems (RDBMS) is the standard method for storing data in a dedicated database, while object-oriented (OO) programming is the default method for business-centric design in programming languages.

  9. CAP theorem - Wikipedia

    en.wikipedia.org/wiki/CAP_theorem

    According to computer scientist Eric Brewer of the University of California, Berkeley, the theorem first appeared in autumn 1998. [9] It was published as the CAP principle in 1999 [10] and presented as a conjecture by Brewer at the 2000 Symposium on Principles of Distributed Computing (PODC). [11]