Glossary
[ Skip navigation ] Show: [ all keywords ] [ A–C ] [ D–H ] [ I–N ] [ O–R ] [ S–Z ]
incomplete specialization | (UML) Some members of a superclass might not be members of any subclass. | subclass.php |
index | (SQL) A data structure that the database uses to find records within a table more quickly. | sql/views.php |
inner join | (SQL) Join of two tables with join attributes specified by the programmer. | jointypes.php |
INSERT INTO | (SQL) Statement to add a row of data to a table. | tables.php |
join (RA) | (RA) Formal definition on which the SQL join is based, the pairwise paste of tuples from the relations being joined. Please see full definition on the page. | sql/join.php |
join (SQL) | (SQL) Operation that links two tables, specified in the FROM clause of a SELECT statement. Please see full definition on the page. | sql/join.php |
join attributes | Attributes whose values are matched during the join operation. | sql/join.php |
join, cross | See cross join. | jointypes.php |
join, natural | See natural join. | jointypes.php |
join, non-equi- | See non-equi-join. | jointypes.php |
join, outer | See outer join. | jointypes.php |
join, self | See self join. | jointypes.php |
junction table | (RM,TM) The table created to hold the linking attributes (FKs) from both sides of a many-to-many association. | manymany.php |
key | See super key. | tables.php |
key, candidate | See candidate key. | keys.php |
key, external | See external key. | keys.php |
key, foreign | See foreign key. | association.php |
key, primary | See primary key. | tables.php |
key, sub | See subkey. | subkeys.php |
key, substitute | See substitute key. | keys.php |
key, super | See super key. | tables.php |
key, surrogate | See surrogate key. | keys.php |
lossless join decomposition | Decomposition (breaking apart) of a relation scheme to eliminate a subkey. The original scheme’s information can be recreated with the join in a query. | subkeys.php |
many-to-many association | (UML) An association with maximum multiplicity of *..* | manymany.php |
materialized view | (SQL) A view that creates and stores a result table in advance of being used. | sql/views.php |
MINUS | (RA,SQL) Operation as defined in set theory, returning the difference of the tuples/rows of two relations/tables over the same scheme. | sql/setops.php |
multiplicity | (UML) The minimum and maximum number of individuals of one class that may be associated with a single member of another class. | association.php |
multivalued attribute | (UML) An attribute that contains more than one value from its domain. This is a design error. | hobbies.php |
named query | (SQL) A view. | sql/views.php |
natural join | (SQL) Join of two tables with the intersection of their schemes used as join attributes. | jointypes.php |
non-equi-join | (SQL) Join based on some condition other than equality of the join attributes. | jointypes.php |
normal form, third | See third normal form. | subkeys.php |
normal forms | (RM) A progression of rules for well-structured database design. | normalize.php |
normalization | (RM) Following a set of rules to insure that a database is well designed. See also normal forms. | subkeys.php |
NULL | (SQL) A special constant value, compatible with any data type, that means "this field does not have any value assigned to it." | phone.php |
[ Skip navigation ] Show: [ all keywords ] [ A–C ] [ D–H ] [ I–N ] [ O–R ] [ S–Z ]