Hussein_ShamsAddin_W2_Databases

[hshamsadd]

No description provided.

[zamanganji]

setupDatabase(dropAndCreate) connects to postgres for DDL and to research_db for everything else. Good separation.
Table creation DDL is valid; self-referencing FK on authors.mentor is fine.
Bridge table authors_papers has a composite PK — perfect.
Inserts look syntactically correct (you escaped Liam O''Connor ).
Joins & basic aggregates will execute.

Double drop/create (wasted work)
Your top-level main() calls setupDatabase(true) and main1() calls setupDatabase(true) again. That recreates the DB twice.
Fix: Drop the first one in main() or the one in main1()—keep just one.
ADD COLUMN is not idempotent
addMentorColumn() will fail on reruns because the column already exists.

[zamanganji]

setupDatabase(dropAndCreate) connects to postgres for DDL and to research_db for everything else. Good separation.
Table creation DDL is valid; self-referencing FK on authors.mentor is fine.
Bridge table authors_papers has a composite PK — perfect.
Inserts look syntactically correct (you escaped Liam O''Connor ).
Joins & basic aggregates will execute.

Double drop/create (wasted work)
Your top-level main() calls setupDatabase(true) and main1() calls setupDatabase(true) again. That recreates the DB twice.
Fix: Drop the first one in main() or the one in main1()—keep just one.
ADD COLUMN is not idempotent
addMentorColumn() will fail on reruns because the column already exists.