Glossary
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| aggregate function | (SQL) Function that operates on a group of rows, for example, SUM. | sql/functions.php |
| aggregation | (UML) An association in which one class represents an assembly of components from one or more other class types. Components may also exist without being part of the assembly. | aggregate.php |
| alias | (SQL) An alternate, short name for a table in the FROM clause of a SELECT statement. | jointypes.php |
| ALTER TABLE | (SQL) Statement to change structure, constraints, or other properties of a table. | tables.php |
| AS | (SQL) Keyword to specify a column alias in the SELECT clause. | sql/functions.php |
| assignment rule | (RM) The association of each attribute in a scheme with its domain. | class.php |
| association | (UML) The way that two classes are functionally connected to each other. | association.php |
| association class | (UML) A class that contains attributes which are the properties of an association rather than a regular class. | manymany.php |
| association, many-to-many | See many-to-many association. | manymany.php |
| association, one-to-many | See one-to-many association. | association.php |
| association, recursive | See recursive association. | recursive.php |
| attribute | (UML,ER,RM) One piece of information that characterizes each member of a class. | class.php |
| attribute, derived | See derived attribute. | manymany.php |
| attribute, descriptive | See descriptive attribute. | class.php |
| attribute, discriminator | See discriminator attribute. | loan.php |
| attribute, multivalued | See multivalued attribute. | hobbies.php |
| attribute, repeated | See repeated attribute. | phone.php |
| base table | (SQL) A table that is referenced by a view definition. | sql/views.php |
| BCNF | (RM) Boyce-Codd normal form: a database with no subkey in any relation (with no exceptions). | subkeys.php |
| candidate key (CK) | (RM) A minimal super key, candidate to become primary key. | keys.php |
| cardinality | (ER) See multiplicity. | association.php |
| Cartesian product | (RA) The result of the join of two relations with no join attributes specified, as defined in set theory. See also cross join. | sql/join.php |
| check constraint | A Boolean condition that the database applies to a row whenever that row is updated or inserted. | constraints/check_constraints.php |
| child | (RM,TM) The relation on the "many" (FK) side of a one-to-many association. | association.php |
| class | (UML) Any "thing" in the enterprise that is to be represented in the database. | class.php |
| column | (TM) See attribute. | tables.php |
| COMMIT | (SQL) Statement to make changes to data permanent. | sql/ddldml.php |
| compatible | (RA) Two schemes are compatible if their intersection is null or if the intersection attributes inherit the same assignment rule from their respective schemes. | sql/join.php |
| complete specialization | (UML) All members of a superclass must also be members of at least one subclass. | subclass.php |
| composition | (UML) Stronger form of aggregation in which components cannot exist without being part of the assembly. | aggregate.php |
| constraint | (RM,TM) Any restriction on the values that can be entered in a table. | tables.php |
| CREATE TABLE | (SQL) Statement to do just what the name implies. | class.php |
| cross join | (SQL) Paste of every pair of tuples from each relation, disregarding join attributes. See also Cartesian product. | jointypes.php |
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