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  2. Join (SQL) - Wikipedia

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

    An inner join (or join) requires each row in the two joined tables to have matching column values, and is a commonly used join operation in applications but should not be assumed to be the best choice in all situations. Inner join creates a new result table by combining column values of two tables (A and B) based upon the join-predicate.

  3. Correlated subquery - Wikipedia

    en.wikipedia.org/wiki/Correlated_subquery

    A GPU acceleration approach is used to significantly improve the performance of the nested method of high algorithmic complexity by exploiting massive parallelism and device memory locality on GPU, [10] which accomplishes the goal for both general-purpose software design and implementation and high performance in subquery processing.

  4. Hash join - Wikipedia

    en.wikipedia.org/wiki/Hash_join

    The hash join is an example of a join algorithm and is used in the implementation of a relational database management system.All variants of hash join algorithms involve building hash tables from the tuples of one or both of the joined relations, and subsequently probing those tables so that only tuples with the same hash code need to be compared for equality in equijoins.

  5. SQL-92 - Wikipedia

    en.wikipedia.org/wiki/SQL-92

    New set operations such as UNION, UNION ALL, CROSS JOIN, and formalized JOIN types (INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL OUTER JOIN). Conditional expressions with CASE. For an example, see Case (SQL). Support for alterations of schema definitions via ALTER and DROP. Bindings for C, Ada, and MUMPS. New features for user privileges.

  6. Sort-merge join - Wikipedia

    en.wikipedia.org/wiki/Sort-merge_join

    The sort-merge join (also known as merge join) is a join algorithm and is used in the implementation of a relational database management system. The basic problem of a join algorithm is to find, for each distinct value of the join attribute, the set of tuples in each relation which display that value. The key idea of the sort-merge algorithm is ...

  7. Recursive join - Wikipedia

    en.wikipedia.org/wiki/Recursive_join

    The recursive join is an operation used in relational databases, also sometimes called a "fixed-point join". It is a compound operation that involves repeating the join operation, typically accumulating more records each time, until a repetition makes no change to the results (as compared to the results of the previous iteration).

  8. Database normalization - Wikipedia

    en.wikipedia.org/wiki/Database_normalization

    This table is in 4NF, but the Supplier ID is equal to the join of its projections: {{Supplier ID, Title}, {Title, Franchisee ID}, {Franchisee ID, Supplier ID}}. No component of that join dependency is a superkey (the sole superkey being the entire heading), so the table does not satisfy the ETNF and can be further decomposed: [ 12 ]

  9. PL/SQL - Wikipedia

    en.wikipedia.org/wiki/PL/SQL

    One can create PL/SQL units such as procedures, functions, packages, types, and triggers, which are stored in the database for reuse by applications that use any of the Oracle Database programmatic interfaces. The first public version of the PL/SQL definition [2] was in 1995. It implements the ISO SQL/PSM standard. [3]