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Two-table comparison

Compare two CSV snapshots by a unique identifier. Separate added, removed, modified, and unchanged records, with field-level before-and-after values.

Fictional sample loaded for demonstration. Your file is not sent to a Rowlane server.

1. Bring in a table

CSV or TSV · UTF-8 text · up to 5 MiB, 20,000 records, and 100 columns

All values stay text, including IDs like 0017.
Quoted commas, quotes, and line breaks are preserved. Choose the delimiter if detection is wrong.
Both starter tables are fictional. Review their headers and keys before running.
Choose a unique identifying field in each snapshot

Loading table…

What this tool does

The first table is the before snapshot and the second is the after snapshot. Choose a unique key in each. Matching is exact. Non-key fields are paired by their exact header text rather than column position. A new or missing column is reported as a difference using [column absent], which differs from an existing empty cell.

How to use it

  1. Read a before table and an after table. Each must have unique headers and a consistent structure.
  2. Choose the identifying column in each table. Blank or repeated keys must be resolved first.
  3. Compare and review one report row per changed field, plus added and removed records.

2. Check the input

Confirm the header and a few records before applying a rule.

Questions

What to expect

Can columns be in a different order?

Yes. Values match by exact header names, so rearranging columns alone does not create a modification.

Why are the modified count and report length different?

Modified counts records. A record with three changed fields produces three report rows.

Review the destination rules. A valid CSV or a clean report does not guarantee that another system will accept the file. Keep your original and verify any export before importing it.