From sub- +‎ query.

subquery (plural subqueries)

1. (databases) A query embedded within a more extensive query, relating only to the data returned by the parent query.

subquery (third-person singular simple present subqueries, present participle subquerying, simple past and past participle subqueried)

1. (databases, transitive) To run a subquery upon.

   We subqueried the customer data to retrieve only customers based in Europe.