Query optimization method and apparatus

A query optimization apparatus, comprising:

• a processor;
• and
• a memory storing instructions executable by the processor,
• wherein the processor is configured to:
• obtain a plurality of query tasks to be optimized, each query task including at least one subtask, and when a same query task includes at least two subtasks, a query dependence relationship existing between the at least two subtasks;
• combine the plurality of query tasks based on the query dependence relationship to obtain a combined task;
• and
• merge at least two subtasks in different query tasks of the plurality of query tasks based on the combined task to obtain a first merged subtask, the first merged subtask being executed to obtain query results of the at least two subtasks in the different query tasks.

A non-transitory computer readable storage medium having stored therein instructions that, when executed by a processor of a device, cause the device to perform a query optimization method, the method comprising:

• obtaining a plurality of query tasks to be optimized, each query task including at least one subtask, and when a same query task includes at least two subtasks, a query dependence relationship existing between the at least two subtasks;
• combining the plurality of query tasks based on the query dependence relationship to obtain a combined task;
• and
• merging at least two subtasks in different query tasks of the plurality of query tasks based on the combined task to obtain a first merged subtask, the first merged subtask being executed to obtain query results of the at least two subtasks in the different query tasks.