Column Diff — Detect Missing Columns and Type Changes

[miladev95]

Describe the feature

• Extend the schema diff to compare model fields against database column metadata.
• modify_column for type/attribute changes (length, precision/scale, unsigned, nullability, default, auto-increment, collation).

Motivation

• Detects schema drift early in CI without side effects.
• Reduces runtime mismatches between models and live schema.
• Provides actionable, reviewable plans toward full migration versioning.

Related Issues

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if you are open to it, I can work on the schema diff feature focused on columns.

[jinzhu]

Hi! Your needs look very similar to something I’m working on — the migrate tool in GORM CLI. I think we can build your requirement on top of that. Could you take a look at the docs and code first? Then we can discuss how to approach the implementation together.

You can find it on the migration branch of cli
README: https://github.com/go-gorm/cli/blob/migration/internal/migration/README.md

[miladev95]

Thanks, i reviewed the code. The column‑diff feature aligns well with the migrate tool. Would you be okay if I open an issue on that repository to track "Column Diff — Detect Missing Columns and Type Changes" and continue the design there?

[jinzhu]

Alright, let’s do it.