● ● The instances below satisfy some constraints Climbers: CId CName Skill Age 123 Edmund EXP 80 214 Arnold BEG 25 313 B
Posted: Fri Jul 01, 2022 5:38 am
- The Instances Below Satisfy Some Constraints Climbers Cid Cname Skill Age 123 Edmund Exp 80 214 Arnold Beg 25 313 B 1 (155.34 KiB) Viewed 37 times
2. delete a tuple
3. Modify a tuple
when modifying pk: it's like adding a new tuple instead of theold one
when modifying fk: must make sure the new value refers to anexiting tuple or is null.
● ● The instances below satisfy some constraints Climbers: CId CName Skill Age 123 Edmund EXP 80 214 Arnold BEG 25 313 Bridget EXP 33 212 James MED 27 Climbs: CId RId Date 123 1 123 3 313 1 214 2 313 1 Duration 10/10/88 5 11/08/87 1 12/08/89 5 08/07/92 2 06/07/94 3 Insert (123, Jeremy, MED, 16) into Climbers? Insert (456, 2, 09/13/98, 3) into Climbs? Delete (313, Bridget, EXP, 33) from Climbers? Modify 123 to 456 in Climbers?