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Question $21$

Let us consider the following relational database.

Songs$($albumID$,$ artistID, songTitle, length$)$

The following SQL query is for retrieving the number of songs with a length of $160$ seconds for each artist

SELECT artistID, COUNT$(*)$

FROM Songs

WHERE length $=\text{'}1160$ sec$\text{'}?$

Which section of the query is illegal?

a$.$ COUNT$(*)$ in the SEI.ECT clause.

b$.$ length in the WHERE clause.

c$.$ The GROUP BY artistID clause should be added.

d$.$ artistID in the SEI BCT clause.