3e_query.txt

π Tournament.name (σ Player.firstname='Aimee' ∧ Player.lastname = 'Lamb' (Player⋈ Player.id=Participation.playerId Participation⋈ Participation.tournamentId=Tournament.id Tournament))


-- The expression begins with joining the Player table with the Participation table on the player IDs, then joins the result with the Tournament table on the tournament IDs. 
The selection operation filters the rows where the player's first name is 'Aimee' and the last name is 'Lamb'.
Finally, the projection operation selects the tournament names from the resulting table.