1) A ......... key is used as a unique ......... to quickly parse data within the ......... A table cannot have more than ......... primary key. a) secondary, value, information, one b) primary, identifier, table, one c) main, key, database, two d) foreign, key, table, three 2) Primary key is used to ......... data uniquely therefore two rows can't have the same primary key. It ......... be null. On the other hand, ......... key is used to maintain relationship between two tables. a) identify, can, foreign b) describe, can, secondary c) identify, can't, foreign d) provide, can't, secondary 3) A primary key is a ......... (or set of .........) in a table that uniquely identifies each ......... in the table. Only one primary key is allowed in a table. a) column, rows, row b) row, columns, row c) row, rows, column d) column, columns, row 4) A ......... key refers to the primary key in another table. It is used to establish a link between the ......... tables. Unlike a primary key, a table ......... have more than one foreign key. a) secondary, two, can't b) primary, two, can c) foreign, two, must d) foreign, two, can 5) Primary key values ......... be deleted from the parent table. Values of foreign key ......... be removed from the child table. The primary key is a ......... index. a) can't, can, clustered b) can, can;t, organised c) can, should, organised d) can't, shouldn't, clustered

Primary key and foreign key

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