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Engineering, 25.03.2020 21:09 volocibel

Consider the following schema:Suppliers (sid: integer, sname: varchar, address: varchar)Parts (pid: integer, pname: varchar, color: varchar)Catalog (sid: integer, pid: integer, cost: real)Where sid is the supplier’s id (primary key in Suppliers), pid is the part’s id (primary key in Parts), and sid together with pid is the primary key of Catalog. The Catalog relation lists the prices charged for parts by Suppliers. A) Write the following queries using relational algebra:5 Find the sids of suppliers who supply every part6. Find the sids of suppliers who supply every red part7. Find the sids of suppliers who supply every red or green part.8. Find the sids of suppliers who supply every red part or supply every green part

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Consider the following schema:Suppliers (sid: integer, sname: varchar, address: varchar)Parts (pid:...
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