# DatabaseConsistency
[](https://badge.fury.io/rb/database_consistency)
[](https://github.com/djezzzl/database_consistency/actions/workflows/tests.yml?query=event%3Aschedule)
[](https://github.com/djezzzl/database_consistency/actions/workflows/rubocop.yml?query=event%3Aschedule)
[](https://opencollective.com/database_consistency#support)
The main goal of the project is to help you avoid various issues due to inconsistencies and inefficiencies between a database schema and application models.
> If the project helps you or your organization, I would be very grateful if you [contribute](https://github.com/djezzzl/database_consistency#contributing) or [donate](https://opencollective.com/database_consistency#support).
> Your support is an incredible motivation and the biggest reward for my hard work.
_The project is greatly supported by [Pennylane](https://www.pennylane.com)! Huge appreciation to the organization, and please join them if you find the gem valuable for you!_
For detailed information, please read the [wiki](docs/wiki/home.md).
Currently, the tool can:
- [find missing null constraints](docs/wiki/ColumnPresenceChecker.md)
- [find missing length validations](docs/wiki/LengthConstraintChecker.md)
- [find missing presence validations](docs/wiki/NullConstraintChecker.md)
- [find missing uniqueness validations](docs/wiki/UniqueIndexChecker.md)
- [find missing foreign keys for `BelongsTo` associations](docs/wiki/ForeignKeyChecker.md)
- [find missing unique indexes for uniqueness validation](docs/wiki/MissingUniqueIndexChecker.md)
- [find missing indexes for `HasOne` and `HasMany` associations](docs/wiki/MissingIndexChecker.md)
- [find primary keys with integer/serial type](docs/wiki/PrimaryKeyTypeChecker.md)
- [find mismatching primary key types with their foreign keys](docs/wiki/ForeignKeyTypeChecker.md)
- [find redundant non-unique indexes](docs/wiki/RedundantIndexChecker.md)
- [find redundant uniqueness constraints](docs/wiki/RedundantUniqueIndexChecker.md)
- [find mismatching enum types with their values](docs/wiki/EnumTypeChecker.md)
- [find mismatching foreign key cascades](docs/wiki/ForeignKeyCascadeChecker.md)
- [find inconsistent values between enums in the database and ActiveRecord's enums/inclusion validations](docs/wiki/EnumValueChecker.md)
- [find redundant `case_sensitive: false` option for unique validations for case-insensitive types](docs/wiki/CaseSensitiveUniqueValidationChecker.md)
- [find missing null constraints on boolean fields](docs/wiki/ThreeStateBooleanChecker.md)
- [find broken associations that refer to non-existent models](docs/wiki/MissingAssociationClassChecker.md)
- [find models that have missing tables](docs/wiki/MissingTableChecker.md)
- [find models with UUID primary keys without specified ordering column](docs/wiki/ImplicitOrderingChecker.md)
- [find belongs_to associations with foreign keys without dependent/on_delete options](docs/wiki/MissingDependentDestroyChecker.md)
- [find polymorphic associations with mismatched foreign key and type null constraints](docs/wiki/PolymorphicAssociationNullabilityChecker.md)
- [find columns used in `find_by` calls that are missing a database index](docs/wiki/MissingIndexFindByChecker.md)
- [find models pointing to views without a primary_key set](docs/wiki/ViewPrimaryKeyChecker.md)
Besides that, the tool provides:
- [auto-correction](docs/wiki/auto-correction.md)
- [flexible configuration](docs/wiki/configuration.md)
- [slow start with TODO files](docs/wiki/generate-todo.md)
- [support of custom checker](docs/wiki/custom-checker.md)
We support the following databases: `SQLite3`, `PostgreSQL` and `MySQL`.
We support [ActiveRecord](https://github.com/rails/rails/tree/master/activerecord) only at the moment.
Please upvote the request for other frameworks if you're interested.
Follow me and stay tuned for the updates:
- [LinkedIn](https://www.linkedin.com/in/evgeniydemin/)
- [Medium](https://evgeniydemin.medium.com/)
- [Twitter](https://twitter.com/EvgeniyDemin/)
- [GitHub](https://github.com/djezzzl)
## Usage
Add this line to your application's Gemfile:
```ruby
gem 'database_consistency', group: :development, require: false
```
And then execute:
```bash
$ bundle install
```
### Example
```bash
$ bundle exec database_consistency
NullConstraintChecker fail User code column is NOT NULL but does not have a validator disallowing nil values
NullConstraintChecker fail User company_id column is NOT NULL but does not have a presence validator for association company
LengthConstraintChecker fail Company note column has a character length limit but does not have a length validator
MissingUniqueIndexChecker fail User name+email model should have a unique index in the database
ForeignKeyChecker fail User company should have a foreign key in the database
ForeignKeyTypeChecker fail User company foreign key (company_id) with type (integer(8)) does not match primary key (id) with type (integer)
MissingIndexChecker fail Company user associated model should have an index in the database
ForeignKeyTypeChecker fail Company user foreign key (company_id) with type (integer(8)) does not match primary key (id) with type (integer)
MissingIndexChecker fail Country users associated model should have an index in the database
ColumnPresenceChecker fail User phone column should be NOT NULL
ColumnPresenceChecker fail User name column is NOT NULL but may receive a NULL value
UniqueIndexChecker fail User index_users_on_name_and_slug index is unique in the database but does not have a uniqueness validator
RedundantUniqueIndexChecker fail User index_users_on_name_and_slug index uniqueness is redundant because (index_users_on_slug) covers it
RedundantIndexChecker fail User index_users_on_phone index is redundant because (index_users_on_phone_and_slug) covers it
ColumnPresenceChecker fail User tmp column (tmp) is missing in table (users) but used for presence validation
ForeignKeyTypeChecker fail User something association (something) of class (User) relies on field (something_id) of table (users) but it is missing
ThreeStateBooleanChecker fail Company active boolean column should have NOT NULL constraint
MissingAssociationClassChecker fail Company anything refers to a non-existent model "Anything"
MissingTableChecker fail LegacyModel should have a corresponding table in the database
ImplicitOrderingChecker fail Secondary::User id setting implicit_order_column is recommended when using UUID as the primary key type
MissingDependentDestroyChecker fail Organization company should have a corresponding has_one/has_many association with dependent option (destroy, delete, delete_all, nullify) or a foreign key with on_delete (cascade, nullify)
MissingIndexFindByChecker fail User email column is used in find_by but is missing an index (found at app/models/user.rb:42)
ViewPrimaryKeyChecker fail ReportView self model pointing to a view should have primary_key set
```
## Funding
### Open Collective Backers
You're an individual who wants to support the project with a monthly donation. Your logo will be available on the Github page. [[Become a backer](https://opencollective.com/database_consistency#backer)]
### Open Collective Sponsors
You're an organization that wants to support the project with a monthly donation. Your logo will be available on the Github page. [[Become a sponsor](https://opencollective.com/database_consistency#sponsor)]
## Contributing
[Bug reports](https://github.com/djezzzl/database_consistency/issues) and [pull requests](https://github.com/djezzzl/database_consistency/pulls) are welcome on GitHub.
This project is intended to be a safe, welcoming space for collaboration, and contributors are expected
to adhere to the [Contributor Covenant](http://contributor-covenant.org) code of conduct.
### Contributors
## Code of Conduct
Everyone interacting in the *DatabaseConsistency* project’s codebases, issue trackers, chat rooms
and mailing lists is expected to
follow the [code of conduct](CODE_OF_CONDUCT.md).
## Changelog
*DatabaseConsistency*'s changelog is available [here](CHANGELOG.md).
## Copyright
Copyright (c) Evgeniy Demin. See [LICENSE.txt](LICENSE.txt) for further details.
