Q13

Consider a relational database containing the following schemas.

\overset{\text{Catalogue}} {\begin{array}{|c|c|c|} \hline \underline{\text{sno}} & \underline{\text{pno}} & \text{cost} \\ \hline S1 & P1 & 150 \\ \hline S1 & P2 & 50 \\ \hline S1 & P3 & 100 \\ \hline S2 & P4 & 200 \\ \hline S2 & P5 & 250 \\ \hline S3 & P1 & 250 \\ \hline S3 & P2 & 150 \\ \hline S3 & P5 & 300 \\ \hline S3 & P4 & 250 \\ \hline \end{array}} \quad \overset{ \text{Suppliers} }{\begin{array}{|c|c|c|} \hline \underline{\text{sno}} & \text{sname} & \text{location} \\ \hline S1 & \text{M/s Royal furniture} & \text{Delhi}\\ \hline S2 & \text{M/s Balaji furniture} & \text{Bangalore} \\ \hline S3 & \text{M/s Premium furniture} & \text{Chennai} \\ \hline \end{array}} \quad \overset{\text{Parts}}{\begin{array}{|c|c|c|} \hline \underline{\text{pno}} & \text{pname} & \text{part_spec} \\ \hline P1 & \text{Table} & \text{Wood} \\ \hline P2 & \text{Chair} & \text{Wood} \\ \hline P3 & \text{Table} & \text{Steel} \\ \hline P4 & \text{Almirah} & \text{Steel} \\ \hline P5 & \text{Almirah} & \text{Wood} \\ \hline \end{array}}

The primary key of each table is indicated by underlining the constituent fields. SELECT s.sno, s.sname FROM Suppliers s, Catalogue c WHERE s.sno=c.sno AND cost > (SELECT AVG (cost) FROM Catalogue WHERE pno = ‘P4’ GROUP BY pno) ; The number of rows returned by the above SQL query is