Draw a relational algebra query tree to retrieve the code and name of each course taught in the second semester, along with the name of the professor who teaches it.
- Add the relations. Place a relation on the canvas from the toolbar, then add a second one. Double-click each relation to name them
COURSESandPROFESSORS. - Filter the courses. Choose Selection from the toolbar and place it above
COURSES, then click Connect to link it to theCOURSESrelation. Click Predicate and typeSemester = 2. - Join. Open the Join menu, select Natural join, and place it above the other elements. Connect it to both the selection operator and
PROFESSORS. - Project. Click Projection and place it above the join. Connect the two operators, then set the projection’s attribute list to
Code, Name, PName. - Close the tree. Click Result, place it at the top and connect it to the projection. Then click Save.
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