1A super key is:AA key with exactly one attributeBAny set of attributes that uniquely identifies tuplesCA foreign key in another tableDThe largest attributeView AnswerDiscussWorkspaceReportSaveEasy
2Which relational algebra operation selects rows that satisfy a condition?AUnion (∪)BSelection (σ)CCartesian product (×)DProjection (π)View AnswerDiscussWorkspaceReportSaveEasy
3If R(A, B) has 5 tuples and S(B, C) has 4 tuples, the maximum number of tuples in R ⋈ S is:A9B4C20D5View AnswerDiscussWorkspaceReportSaveMedium
4Referential integrity ensures that:AEvery foreign key value matches an existing primary key (or is NULL)BTables are normalisedCData is encryptedDPrimary keys are uniqueView AnswerDiscussWorkspaceReportSaveEasy
5Which relational algebra operation removes duplicate columns and keeps only specified attributes?ASelection (σ)BDivision (÷)CProjection (π)DJoin (⋈)View AnswerDiscussWorkspaceReportSaveMedium