Core Commands¶

The core commands provide essential data quality operations for validation, profiling, and data protection.

Overview¶

Command	Description	Primary Use Case
`learn`	Learn schema from data	Schema inference
`check`	Validate data quality	Data validation
`scan`	Scan for PII	Privacy compliance
`mask`	Mask sensitive data	Data anonymization
`profile`	Generate data profile	Data exploration
`read`	Read and preview data	Data inspection
`compare`	Detect data drift	Model monitoring

Typical Workflow¶

graph LR
    A[Raw Data] --> B[learn]
    B --> C[schema.yaml]
    A --> D[check]
    C --> D
    D --> E{Issues?}
    E -->|Yes| F[Fix Data]
    E -->|No| G[scan]
    G --> H{PII Found?}
    H -->|Yes| I[mask]
    H -->|No| J[Ready]
    I --> J

1. Schema Learning¶

First, learn a schema from your reference data:

truthound learn reference_data.csv -o schema.yaml

2. Data Validation¶

Validate new data against the schema:

truthound check new_data.csv --schema schema.yaml --strict

3. PII Detection¶

Scan for personally identifiable information:

truthound scan customer_data.csv

4. Data Masking¶

Mask sensitive columns before sharing:

truthound mask customer_data.csv -o safe_data.csv --strategy hash

5. Data Profiling¶

Generate statistical profile for analysis:

truthound profile data.csv --format json -o profile.json

6. Drift Detection¶

Compare datasets to detect distribution changes:

truthound compare baseline.csv production.csv --method psi

Common Options¶

All core commands share these common patterns:

Output Format (`-f, --format`)¶

# Console output (default)
truthound check data.csv

# JSON output
truthound check data.csv --format json

# HTML report
truthound check data.csv --format html -o report.html

Output File (`-o, --output`)¶

truthound check data.csv -o results.json --format json

Strict Mode (`--strict`)¶

Exit with code 1 if issues are found (useful for CI/CD):

truthound check data.csv --strict
truthound compare baseline.csv current.csv --strict

Data Source Options¶

All core commands accept data source options for reading directly from databases instead of files. When using these options, the file argument becomes optional.

Option	Short	Description
`--connection`	`--conn`	Database connection string (e.g., `postgresql://user:pass@host/db`)
`--table`		Database table name
`--query`		SQL query (alternative to `--table`)
`--source-config`	`--sc`	Path to a data source config file (JSON/YAML)
`--source-name`		Custom label for the data source

# Validate a database table directly
truthound check --connection "postgresql://user:pass@host/db" --table users --strict

# Profile from a source config file
truthound profile --source-config prod_db.yaml

# Read and preview database data
truthound read --connection "sqlite:///data.db" --table orders --head 20

For full details on connection string formats, config files, and security best practices, see the CLI Data Source Guide.

CI/CD Integration¶

Use core commands in your CI/CD pipeline:

# GitHub Actions example
- name: Validate Data Quality
  run: truthound check data/*.csv --strict

- name: Check for PII
  run: truthound scan data/*.csv --format json -o pii_report.json

Next Steps¶

read - Read and preview data
learn - Learn schema from data
check - Validate data quality
scan - Scan for PII
mask - Mask sensitive data
profile - Generate data profile
compare - Detect data drift