Specify the following queries based on the database schema using operations of relational algebra

Опубликовано: 04 Ноябрь 2024
на канале: Computer Engineering life
789
10

00:00 Example 1
01:43 Example 2
02:37 Example 3
04:27 Example 4

ERRORS:
-2: In part 2, missing initial projection for “DEPENDENT” table for “ESSN” and “DEPENDENT_NAME”.
-2: In part 2, there is an incomplete join. Must include “SSN=ESSN”.
-2: In part 2, there is an incomplete join. Must include “FNAME=DEPENDENT_NAME”.
-2: In part 4, must rename the attribute of the immediate result for “Social_anna”.
-7: In part 4, missing join operation and join conditions.
Total Points Lost: 15.0

2. D ← πDEPENDENT_NAME, ESSN DEPENDENT
RESULT← EMPLOYEE ⋈SSN = ESSN AND FNAME=DEPENDENT_NAME D

4. anna ← σFNAME = “Anna” and LNAME = “Hunter(EMPLOYEE)
Social_anna(assn) ← πSSN(anna)
Supervised ← Social_anna ⋈assn = SUPERSSN EMPLOYEE
Result ← πLNAME, FNAME(Supervised)


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Notes:
https://docs.google.com/document/d/1T...