SQL Fundamentals

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Lab6 objectives100 XP

04.Translate Selections

Each task gives an expression. Write the SQL that returns the same relation.

Algebra	SQL
`σ condition (r)`	`SELECT * FROM r WHERE condition`
`∧` `∨` `¬`	`AND` `OR` `NOT`
`≠` `≤` `≥`	`<>` `<=` `>=`

σ dept_name = 'Music' (instructor)
σ dept_name = 'Comp. Sci.' ∧ salary > 80000 (instructor)
σ credits = 3 ∨ dept_name = 'Physics' (course)
σ ¬(building = 'Champlain') (department)
Before you run it: how many tuples does σ tot_cred ≥ 60 (student) return?
Run it to check.

Something unclear, wrong or missing?

Databaselab-db · PostgreSQL in your browser 0:00

SELECT * FROM instructor;

Ctrl↵runs the query · select text to run part of it

Objective 1 of 60/6 done

σ dept_name = 'Music' (instructor)
Every attribute of the instructors in Music.