A、Table
B、Index
C、View
D、Transaction
A、Select, Project
B、Cartesian-Product, Project
C、Cartesian-Product, Select, Project
D、Cartesian-Product, Select
A、Select, Project, Cartesian-Product
B、Union, Project, Cartesian-Product
C、Select, Rename, Cartesian-Product
D、Set difference, Project, Cartesian-Product
A、There is no order on the rows.
B、There is no order on the columns.
C、Two tuples can be identical in all column values.
D、Multi-valued attributes are not permitted.
A、Entity integrity
B、Referential integrity
C、Check constraint
D、User defined constraint
A、DBMS
B、Database
C、Database application
D、Data Schema
A、( A, B )
B、( A, C )
C、( B, D )
D、( B, C)
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