another name for a column in a table.
MySQL statement that automatically assigns surrogate key numbers. The starting value may be any number but the increment wil always be 1.
a relation in third normal form in which every determinant is a candidate key:.
an attribute or a group of attributes that identifies a unique row in a relation. One of these will be chosen to be the primary key.
a logical group of bytes in a row of a relation or a table. It has the same meaning for every row of the relation.
a key of a relation that consists of two or more columns:.
a structure described in a formal language supported by the database management system (DBMS). In a relational database, it defines the tables, the fields, relationships, views, indexes, packages, procedures, functions, queues, triggers, types, sequences, materialized views, synonyms, database links, directories, and other elements.
one or more attributes that functionally determine another attribute or attributes. In the functional dependancy (A,B) -> D,C, the attributes (A,B) is called this:.
something of importance to the user that needs to be represented in the database:.
a logical group of bytes in a record used with file processing. In context of relational mode, it is a synonym for 'attribute'.
a term for table in traditional data processing:.
any table that fits the definition of a relation:.
an attribute that is a key of one or more relations orther than the one in which it appears:.
a relationship between attributes in which one attribute or group of attributes determines the value of another. .
the starting value of a surrogate key:.
a group of one or more attributes that identify a unique row in a relation. Because relations cannot have duplicate rows, every relation must have at least one of these that is the composite of all the attributes in the relation.
a condition in a relation with three or more attributes in which independent attributes appear to have relationships they do not have:.
a key that potentially identifies more than one row:.
the process of evaluating a relation to determine whether it is in a specified normal form and, if necessary, of converting it to relations in that specified normal form.
the process of evaluating a relation to determine whether it is in a specified normal form and, if necessary, of converting it to relations in that specified normal form:.
an attribute value that has never been supplied. Such values are ambiguous and can mean the value is unknown, the value is not appropriate, or hte value is know to be blank.
a candidate key selected to be the key of a relation:.
a group of fields pertaining to the same entity; used in file-processing systems. In a relational model, a synonym for a row and tuple:.
a relationship constraint on foreign key values. A referential integrity constraint specifies that the values of a foreign key must be a proper subset of the values of the primary key to which it refers.
a two-dimensional table that has characterstics such as; rows contain data about the entity, columns contain data about attriburtes of the entity, cells of the table hold a single value, no two roys may be identical..etc.
a group of columns in a table. All the columns here pertain to the same entity. This is also known as a tuple or record:.
a unique, system-supplied identifier used as the primary key of a relation. The values have no meaning to the users and usually are hidden on forms and reports:.
a key that identifies a unique row:.
the amount that is added to each key value to create the next key value:.
another term for a relation:.
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