1) In database design, an entity refers to.... a) a real-world object that can be identified and stored in a database b) a type relationship between two tables c) a calculation performed on a table d) a field that stores numerical values 2) Which of the following is an example of an entity in a school database? a) student b) registers c) has d) date of birth 3) In an entity relationship diagram, attributes are shown as.... a) rectangles b) ovals c) diamonds d) arrows 4) A primary key in an entity relationship is used to... a) link one entity to another b) identify each record uniquely c) store foreign data d) store metadata 5) In an entity relationship diagram, relationships are represented by....  a) ovals b) diamonds c) rectangles d) lines only 6) Which of the following describes "cardinality" in an entity relationship model? a) the number of attributes an entity can have b) the number of rows in a table c) the number of instances of one entity related to another d) the number of tables in a database 7) In a one-to-many, (1:M) relationship, the 'one' side is usually represented in a table by: a) a primary key b) a foreign key c) a composite key d) a candidate key 8) A foreign key is.... a) a key that exists in two or more tables and creates a link b) a key that stores encrypted data c) the main key of the database d) a duplicate primary key 9) Which of the following is an example of a many-to-many (M:N) relationship? a) student an course b) teacher and identity card c) country and capital d) school and principal 10) A weak entity is one that.... a) cannot be uniquely identified without a related strong entity b) has no attributes c) has no relationship d) contains only text data

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