Snapshot-based data tracing method and system

The invention discloses a snapshot-based data tracing method and system. The method comprises the steps of modifying a capture table and a task, obtaining an output target table of a to-be-updated task script, obtaining a dependent upstream table of the output target table, obtaining field data consanguinity from a task snapshot script, and collecting table updates from the latest capture table modification; updating the data consanguinity, obtaining the latest historical snapshot of the to-be-updated task, refreshing the corresponding relationship between the output target table and the task snapshot, refreshing the corresponding relationship between the task snapshot and the input source end table, and refreshing the table change record; and obtaining a data source, a data destination and a data processing process by updating the data consanguinity. The method has the multi-table, multi-field and multi-version traceability, traces the generation process of data based on the table snapshots and the task snap