Databases
Revision as of 22:34, 19 June 2020 by Adelo Vieira (talk | contribs)
Terminology of relational model
A database is an organized collection of data. It is the collection of schemas, tables, queries, reports, views, and other objects. https://en.wikipedia.org/wiki/Database
- What is the primary key: title_id
- What is the foreign key: Pub_id
- What is the cardinality: 13
- select count(title_id) as 'Cardinality of the «titles» table' from titles;
- What is its degree: 9
- What is the domain of contract: Smallint(6) NOT NULL
- What is the domain of country in the table Publishers: varchar(15) NOT NULL
MySQL
