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

A system, comprising:

• a hardware processor;
• a memory, coupled to the hardware processor and storing one or more instructions that, when executed by the hardware processor, cause the system to implement steps of:
• configuring data source feature information into an external storage space of a query engine;
• importing the data source feature information from the external storage space of the query engine into an internal storage space of the query engine, wherein a data source corresponding to the data source feature information referenced by a structured query language (SQL) is queried by obtaining identification information of the data source;
• reading, from the internal storage space of the query engine based on the identification information of the data source, the data source feature information corresponding to the data source;
• decomposing the SQL into logical plans based on the data source feature information to obtain a logical plan set, wherein the data source feature information is stored in the 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;
• and
• executing the physical plan to obtain a query result of the SQL to return to a user.

A non-transitory computer-readable storage medium storing one or more instructions that, when executed by a hardware processor, cause the hardware processor to:

• store data source feature information imported from an external storage space of a query engine in an internal storage space of the query engine;
• obtain identification information of a data source referenced by a structured query language (SQL) from a user;
• read, from the internal storage space of the query engine based on the identification information of the data source, the data source feature information corresponding to the data source referenced by the SQL;
• decompose the SQL, into logical plans based on the data source feature information, to obtain a logical plan set;
• generate physical plans for the logical plan set based on the data source feature information, to obtain a physical plan set;
• determine query costs of the physical plan set based on the data source feature information to obtain a physical plan;
• and
• execute the physical plan to obtain a query result to return to the user.