Query processing method, data source registration method, and query engine

A query processing method including decomposing an SQL into logical plans based on data source feature information, to obtain a logical plan set, where the data source feature information is stored in an internal storage space of the query engine; generating physical plans for the logical plan set based on the data source feature information, to obtain a physical plan set; determining query costs of the physical plan set based on the data source feature information, to obtain a physical plan with a highest priority; and executing the physical plan with the highest priority, to obtain a query result queried by a user.