For example, the cardinality of relation “Student” is 2 as there are 2 tuples in the table. Roll_noĬardinality : The number of tuples in a relation is called the Cardinality of the relation. For example, the relation “Student” given below with four attributes is a relation of degree 4. For example, in “Student” relation given above, the attribute Roll_no takes integer values and hence its domain is a set of integer values.ĭegree : The number of attributes in a relation is called the Degree of the relation. Usually, a data type is used to specify domain for an attribute. for example In the table “Student” given above, there are two tuples.ĭomain : It is a set of values from which an attribute can take a value in each row. Tuple : Each row of data in a relation (table) is called a tuple. for example : In the table “Student” given below, there are four attributes. Some applications are given below :ĭatabase Concepts Class 11 Notes Common Terms used in DBMS :Īttributes : The columns of a relation are the attributes which are also referred as fields. Some examples of open source and commercial DBMS include MySQL, Oracle, PostgreSQL, SQL Server, Microsoft Access, MongoDB etc.ĭatabases are widely used in various fields.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |