CSV SafePreview / import guide

CSV import preflight before SQL generation

Import preflight is a short review of the problems that make a spreadsheet export surprising at the database boundary. It catches structural errors and highlights assumptions before a query is generated.

What to check

Row shape: every data row should have the same number of fields as the header.
Headers: blank, duplicated, or whitespace-polluted names should be reviewed before they become identifiers.
Values: empty strings, whitespace, and mixed numeric/text values can change inferred types or NULL behavior.
Transport: BOMs, mixed line endings, and alternate delimiters can change how another importer reads the file.

Worked example

id, id ,status
 1,2,ready
3,,false

SafePreview reports the repeated header, header whitespace, value whitespace, empty-value/NULL semantics, and mixed-type fallback. It does not silently rename the source or discard a row.

Use the local suite

Analyze a sample CSV in your browser, review the inferred schema, generate a conservative PostgreSQL or SQLite preview, and download a local readiness report.

The tool is diagnostic, not a database connection, schema guarantee, migration service, or production-import approval. CSV text stays in the browser.

Read the PostgreSQL-specific guide · Check PostgreSQL COPY assumptions · Return to CSV SafePreview