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  2. Join (SQL) - Wikipedia

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

    If NULL join columns are to be deliberately removed from the result set, an inner join can be faster than an outer join because the table join and filtering is done in a single step. Conversely, an inner join can result in disastrously slow performance or even a server crash when used in a large volume query in combination with database ...

  3. Surrogate key - Wikipedia

    en.wikipedia.org/wiki/Surrogate_key

    To discover such errors, one must perform a query that uses a left outer join between the table with the foreign key and the table with the primary key, showing both key fields in addition to any fields required to distinguish the record; all invalid foreign-key values will have the primary-key column as NULL. The need to perform such a check ...

  4. Block nested loop - Wikipedia

    en.wikipedia.org/wiki/Block_nested_loop

    A block-nested loop (BNL) is an algorithm used to join two relations in a relational database. [1]This algorithm [2] is a variation of the simple nested loop join and joins two relations and (the "outer" and "inner" join operands, respectively).

  5. 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.

  6. 15 holiday gifts for dementia patients and caregivers ...

    www.aol.com/15-holiday-gifts-dementia-patients...

    6. Music playlists can be compiled with your loved one’s favorite artists and songs. 7. Comfy, loose-fitting clothing, like sweatsuits, slip-on shirts, night gowns, bathrobes and lace-free shoes ...

  7. What is the 2024 Oxford Word of the Year? - AOL

    www.aol.com/2024-oxford-word-124548327.html

    Adopted by Gen Z and Gen Alpha, it gained new prominence in 2024, according to Oxford, as a term used to capture concerns about the impact of consuming excessive amounts of "low-quality online ...

  8. Relational algebra - Wikipedia

    en.wikipedia.org/wiki/Relational_algebra

    The right outer join ( ) behaves almost identically to the left outer join, but the roles of the tables are switched. The right outer join of relations R and S is written as R S . [ e ] The result of the right outer join is the set of all combinations of tuples in R and S that are equal on their common attribute names, in addition to tuples in ...

  9. Nested loop join - Wikipedia

    en.wikipedia.org/wiki/Nested_loop_join

    algorithm nested_loop_join is for each tuple r in R do for each tuple s in S do if r and s satisfy the join condition then yield tuple <r,s> This algorithm will involve n r *b s + b r block transfers and n r +b r seeks, where b r and b s are number of blocks in relations R and S respectively, and n r is the number of tuples in relation R.