Abstract: A plan execution method, apparatus, and system for a distributed database are provided. The plan execution method is performed by a first execution thread on a plan execution node. Feedback data returned by a child logical subplan of a current logical subplan is received in parallel with at least one second execution thread scheduled to execute the current logical subplan. Whether the current logical subplan includes an execution operator related to a row number generation operation is determined. In response to that the current logical subplan includes the execution operator related to a row number generation operation, the received data are cached, and a row number start value obtaining request is sent to the scheduling node. Data row numbers are generated for the cached data based on a received row number start value.

Abstract: A plan execution method, apparatus, and system for a distributed database are provided. The plan execution method is performed by a first execution thread on a plan execution node. Feedback data returned by a child logical subplan of a current logical subplan is received in parallel with at least one second execution thread scheduled to execute the current logical subplan. Whether the current logical subplan includes an execution operator related to a row number generation operation is determined. In response to that the current logical subplan includes the execution operator related to a row number generation operation, the received data are cached, and a row number start value obtaining request is sent to the scheduling node. Data row numbers are generated for the cached data based on a received row number start value.

Abstract: Embodiments of this specification provide a table data query method, a table data query apparatus, and a system that are of a distributed database. In response to that a table data processing node executes a first execution subplan to read row data of a driving table, the table data query apparatus generates a data rescanning instruction or a data scanning instruction based on whether a cache apparatus of the table data processing node caches the read row data, and sends the data rescanning instruction or the data scanning instruction to a driven table scanning scheduling apparatus of the table data processing node. The driven table scanning scheduling apparatus obtains a driven table data query result based on the data rescanning instruction or the data scanning instruction, and returns the driven table data query result to the table data query apparatus.

Abstract: Embodiments of this specification provide a table data query method, a table data query apparatus, and a system that are of a distributed database. In response to that a table data processing node executes a first execution subplan to read row data of a driving table, the table data query apparatus generates a data rescanning instruction or a data scanning instruction based on whether a cache apparatus of the table data processing node caches the read row data, and sends the data rescanning instruction or the data scanning instruction to a driven table scanning scheduling apparatus of the table data processing node. The driven table scanning scheduling apparatus obtains a driven table data query result based on the data rescanning instruction or the data scanning instruction, and returns the driven table data query result to the table data query apparatus.