Tag default:'null' always causes field migration

[Nomango]

GORM Playground Link

No time to make it for now

Description

default:null and default:'null' are being treated the same when field migrating.

The reason is this line:

gorm/migrator/migrator.go

Line 490 in 7da24d1

currentDefaultNotNull := field.HasDefaultValue && !strings.EqualFold(field.DefaultValue, "NULL")

field.DefaultValue is equal to null in both two cases.

Maybe it should change to

currentDefaultNotNull := field.HasDefaultValue && field.DefaultValueInterface != nil

[github-actions]

The issue has been automatically marked as stale as it missing playground pull request link, which is important to help others understand your issue effectively and make sure the issue hasn't been fixed on latest master, checkout https://github.com/go-gorm/playground for details. it will be closed in 30 days if no further activity occurs. if you are asking question, please use the Question template, most likely your question already answered https://github.com/go-gorm/gorm/issues or described in the document https://gorm.io ✨ Search Before Asking ✨

[github-actions]

The issue has been automatically marked as stale as it missing playground pull request link, which is important to help others understand your issue effectively and make sure the issue hasn't been fixed on latest master, checkout https://github.com/go-gorm/playground for details. it will be closed in 30 days if no further activity occurs. if you are asking question, please use the Question template, most likely your question already answered https://github.com/go-gorm/gorm/issues or described in the document https://gorm.io ✨ Search Before Asking ✨