Sales operations · Salesforce Data Loader preflight
Salesforce Task/Event Upsert Preflight
Check a Task or Event CSV before an Update or Upsert. Find Duplicate Id Specified risks by batch and resolve polymorphic references using your own local lookup export.
Files and lookup values stay in this browser. No Salesforce connection, upload, account or retained source file. This tool cannot check live records, permissions, validation rules or perform an import.
1. Add your activity CSV
No activity file selected.
Source lines are the physical starting lines of CSV records; quoted multiline cells retain their original references. Empty physical lines are skipped, while delimiter-filled blank records are retained.
4. Optional local lookup map
Supply a CSV with exact external keys and Salesforce IDs that you already resolved. Matching preserves external-key case and whitespace. Duplicate keys remain ambiguous even when both IDs are equal.
No lookup file selected.
How to interpret these checks
File-certain failures: a missing Update ID, malformed ID, duplicate Upsert external key, or repeated record ID inside one batch needs correction. Batch assignment counts data records, not physical CSV lines.
Cross-batch duplicates are a potential overwrite trace. The last file-ordered row is a forecast conditional on execution order and success, not a guaranteed final Salesforce value. Mixed same-batch and cross-batch groups have no predicted winner.
A structurally valid ID does not prove that a record exists or belongs to the correct relationship type. External-key uniqueness, create versus update, permissions, validation rules and concurrent changes remain unknown without tenant evidence.
Data Loader does not support external-ID mapping on polymorphic fields. Use already-resolved Salesforce IDs or review Workbench / Dataloader.io support for your workflow. The tool does not contact those services.