"Composite Key Order and INCLUDE"

1. What is the primary rule for the order of columns in a composite key index?

Equality predicates first, then one range predicate, then ORDER BY columns, and finally INCLUDE columns ORDER BY columns first, then equality predicates, followed by one range predicate In any order as long as they are all included All columns should be included without concern for order

2. Why is it important to have only one range predicate in a composite key index?

It allows for multiple indexed columns to narrow down the search efficiently It prevents the index from being too large and slow to traverse Once a range column is reached, additional range columns cannot narrow the search further It automatically makes the index cover all SELECT statements

3. In the context of SQL indexing, what is the effect of placing a wide column in the INCLUDE section?

It increases the B-tree size and traversal time It is kept at every level of the B-tree It only affects the leaf level, reducing overall size impact It is not allowed in the INCLUDE section

4. If an index is defined on (A, B, C), which of the following queries will it NOT effectively support?

Filtering on A and B Filtering on A only Filtering on B only Filtering on B and C

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