Homework2Sol

# Psidpidcatalogppidparts

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Unformatted text preview: een’Parts) Catalog) 3. Find the sids of suppliers who supply some red part or are at 221 Packer Street. ρR1(psid (ppid(scolor=’red’ Parts) Catalog)) ρR2(psid(saddress=’221PackerStreet’ Suppliers)) R1R2 4. Find the sids of suppliers who supply every part. (psid, pid Catalog)/ (ppid Parts) 5. Find the sids of suppliers who supply every red part. (psid, pid Catalog)/ (ppidscolor=’red’ Parts) 6. Find the sids of suppliers who supply every red or green part. (psid, pid Catalog)/ (ppidscolor=’red’ ∨color=’green’Parts) 7. Find the sids of suppliers who supply every red part or supply every green part. ρR1(((psid, pid Catalog)/ (ppidscolor=’red’ Parts))) ρR2(((psid, pid Catalog)/ (ppidscolor=’green’ Parts))) R1R2 8. Find pairs of sids such that the supplier with the first sid charges more for some part than the supplier with the second sid. ρR1(Catalog) ρR2(Catalog) p R1.sid, R2.sid(sR1.pid=R2.pid∧R1.sid≠R2.sid∧R1.cost&gt;R2.cost(R1 × R2)) 9. Find the pids of parts supplied by at least two different suppliers. ρR1(Catalog) ρR2(Catalog) p R1.pidsR1.pid=R2.pid∧R1.sid≠R2.sid(R1 × R2) 10. Find the pids of the most expensive parts supplied by suppliers named Yosemite Sham. ρR1(psids sname =’Yosemite Sham’Suppliers) ρR2(R1 Catalog) ρR3(R2) ρR4(1 → s...
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