Validate

Detect mixed data types and format inconsistencies within CSV columns

Audit CSV columns to detect mixed data types, inconsistent formats, and type anomalies.

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Why Onfyt: Detects format-level inconsistencies within a single column (three different date formats, mixed numeric and text) rather than just comparing across columns.

Interactive Sample Data

idvaluedate
11002024-01-15
2n/a15/01/2024
3200Jan 15, 2024

How this tool works

Schema drift accumulates silently. An amount column that started as plain integers acquires "N/A" strings from one team, "n/a" from another, and decimal fractions from a third. A date column receives entries in ISO 8601 from the engineering export, MM/DD/YYYY from the US sales team, and DD/MM/YYYY from the UK office. Running SUM or GROUP BY against a column with mixed types produces a type error at best, or silently wrong numbers at worst — and both outcomes are difficult to trace back to their cause without a consistency report. DataFix profiles each column across all rows, determines the dominant type (string, integer, float, date, boolean), and reports every row that deviates from it. This is a diagnostic tool: it tells you where type inconsistencies exist so you can decide the appropriate fix. Jagged CSV files—where specific rows have fewer or more delimiters than the header row—are a leading cause of pipeline failures in cloud data warehouses like Snowflake, BigQuery, and Databricks. Inconsistent column counts typically occur when unescaped commas exist in user-submitted comments or when line breaks break row boundaries. DataFix audits every row against the header dimensionality, flagging rows with field mismatches, displaying expected versus actual column counts, and isolating the exact line numbers where parsing breaks down. Uneven field counts caused by unescaped line breaks or rogue commas corrupt downstream data pipelines, causing batch jobs to fail in Snowflake or BigQuery. Highlighting rows with ragged delimiter counts pinpoints unescaped commas before database loaders abort the entire batch.

Things that usually go wrong

  • A column with 99% numeric and 1% text values is reported as inconsistent — review those text values.
  • Date columns with mixed formats are flagged as inconsistent.

Edge cases we tested

🧪 Column is 50/50 numeric and string

Reports 'ambiguous type'; both types listed with counts.

🧪 Boolean column with 'True', '1', 'yes' mixed

All flagged as boolean variants; dominant representation identified.

🧪 Scientific notation ('1.2e5') alongside plain integers

Normalised to float type; not flagged as anomaly.

Frequently Asked Questions

What types are checked?

Integer, float, date, boolean, and text. Mixed-type columns are flagged.

Does it auto-fix inconsistencies?

Not automatically. The report shows which rows and columns are inconsistent. Use Find and Replace or type conversion tools to fix.

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