Bulk Import -- Validation & Dry Run
Bulk Import executes a validation phase before any data is written to live tables.
This phase exists to detect structural and data-level errors without mutating production data.
Structural Validation
Performed immediately after ZIP upload.
Validates:
- ZIP integrity
- CSV format (RFC 4180)
- File naming vs table API names
- Presence of mandatory columns
- Column name validity vs schema
Structural validation failure blocks the import from continuing.
Dry Run Execution
After passing structural validation, a dry run is executed on temporary tables.
The dry run simulates:
- Identifier resolution
- Relation resolution
- Type conversion
- Row-level mutation outcomes
No data is written to live tables.
Error Characteristics
- Errors are recorded per row
- Errors do not block other rows from being evaluated
- Failed rows do not block scheduling
- All detected errors are downloadable as structured error reports
Guarantees
- A successful dry run does not guarantee a successful final import
- Live data may change between dry run and execution
- The dry run does not reserve identities or relations