Question: ( b ) Consider the SQL query shown in Table 1 . ( i ) Draw a near - optimal query tree for the SQL

(b) Consider the SQL query shown in Table 1.(i) Draw a near-optimal query tree for the SQL query. (ii) Identify the root and leaf nodes in the tree that you drew for part (i).(iii) Write down a justification for the position of the root node and each of the
internal nodes in the tree that you drew for part (i) in terms of the heuristic
steps that optimisers apply to reduce the cost of optimisation. Explain why
the position of the nodes should make the query efficient. SELECT factory.name
FROM factory, order
WHERE order.factory_ID=factory.ID
AND order.quantity >20
AND order.priority=urgent; Table 1: An SQL query about orders placed with a factory.

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