Import Preprocessing APL Code

Primarily used for batch preloading and preprocessing all import data before the actual import operation.

1. The import preprocessing APL code executes before the import validation APL code
2. During preprocessing, data is processed in batches (20 records per batch) stored in context.dataList
3. Complex import validation logic can be pre-calculated in the preprocessing APL code and written to cache
4. The validation results can then be retrieved from cache during import validation APL code execution

Import Validation APL Code

Mainly used for functional validation of data before import.

1. Similar to create/edit pre-validation functions, it can display validation messages and support blocking operations
2. If data import fails or validation errors occur, error messages will be populated in the Excel failure list