Microsoft Exam DP-420 Topic 3 Question 4 Discussion

If a query has a filter with two or more properties, adding a composite index will improve performance.

Consider the following query:

SELECT * FROM c WHERE c.name = ''Tim'' and c.age > 18

In the absence of a composite index on (name ASC, and age ASC), we will utilize a range index for this query. We can improve the efficiency of this query by creating a composite index for name and age.

Queries with multiple equality filters and a maximum of one range filter (such as >,<, <=, >=, !=) will utilize the composite index.