title: “Version Source Verification” description: “How AlphaDB verifies a version source before migrating: issue priorities (low, high, critical) and every structural and column check it runs.”

Version Source Verification

AlphaDB includes a powerful verification system that scans your version source for errors and potential issues before you apply any changes to your database. This helps prevent common mistakes, ensures your schema is valid, and can save you from unintended data loss.

Verification is run automatically when you use the update command, but you can also run it manually through the CLI, Rust, Python, or Node.js APIs.

Issue Priorities

When the verifier finds an issue, it assigns one of three priority levels:

- LOW: The operation will likely succeed, but it might not have any effect, or there might be a better way to do it. For example, a createtable block that doesn’t define any tables. - HIGH: The operation will still work, but it might produce a different result than you intended. For example, using an unknown method name like createtablee instead of createtable. - CRITICAL: The operation will fail and will not be executed. This could be due to a syntax error, a logical impossibility (like a primary key that doesn’t exist), or something that could cause data loss.

What is Verified?

The verifier checks for a wide range of issues, including:

1. Root-Level Structure

- Missing engine: Every version source used by the CLI must specify an engine. Supported values are postgres and mysql. - Missing name: Every version source must have a name at the root level. - Missing version array: The version array must exist, even if it’s empty.

2. Version-Level Structure

- Missing _id: Every version object inside the version array must have an _id. - Invalid _id: The _id must be a valid version number string (e.g., "1.0.0"). - Unknown methods: The verifier will flag any methods that don’t exist (e.g., altertablee).

3. Table and Column Logic

- Primary key validity: In a createtable block, the specified primary_key must match the name of a column defined in the same table. - Dropping a primary key: The verifier will warn you if you try to drop a column that is currently the primary key of a table.

4. Column Attribute Compatibility

Certain column attributes cannot be used together. The verifier will flag these critical errors:

- An auto-incrementing column (generated on PostgreSQL, auto_increment on MySQL) cannot allow NULL. - Engine-specific attributes must be used with compatible column types.

The exact rules per engine are listed on the PostgreSQL and MySQL syntax pages.

By catching these issues early, AlphaDB helps you write clean, reliable, and safe database schemas.