API Design · Middle · Question 16 of 75

How can an API offer flexible filtering without becoming a query language nobody can optimize?

1Accept raw SQL in a query parameter
2Allow filtering on every field with every operator
✓Correct answer: Support a defined set of filterable fields and operators that are backed by indexes, and reject the rest

Explanation

Unbounded filters lead to slow queries and denial of service. Google's AIP-160 defines a constrained filter syntax.

Further reading

Test yourself

Take the API Design · Middle quiz: questions and options are shuffled, and you get a review of your mistakes at the end.