Skillshub generating-orm-code

install

source · Clone the upstream repo

git clone https://github.com/ComeOnOliver/skillshub

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/ComeOnOliver/skillshub "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/jeremylongshore/claude-code-plugins-plus-skills/generating-orm-code" ~/.claude/skills/comeonoliver-skillshub-generating-orm-code && rm -rf "$T"

manifest: skills/jeremylongshore/claude-code-plugins-plus-skills/generating-orm-code/SKILL.md

ORM Code Generator

Overview

Generate type-safe ORM model classes, migration files, and repository patterns from existing database schemas or domain specifications. Supports Prisma, TypeORM, Sequelize, SQLAlchemy, Django ORM, and Drizzle ORM.

Prerequisites

Database connection string or credentials for schema introspection
```
psql
```
or
```
mysql
```
CLI for querying
```
information_schema
```
Target ORM framework already installed in the project (
```
prisma
```
,
```
typeorm
```
,
```
sqlalchemy
```
, etc.)
Node.js/Python/Go runtime matching the target ORM
Existing project structure to place generated models in the correct directory

Instructions

Introspect the database schema by querying
```
information_schema.COLUMNS
```
,
```
information_schema.TABLE_CONSTRAINTS
```
, and
```
information_schema.KEY_COLUMN_USAGE
```
to extract all tables, columns, data types, nullable flags, defaults, primary keys, foreign keys, and unique constraints.
For PostgreSQL, additionally query
```
pg_catalog.pg_type
```
for custom enum types and
```
pg_catalog.pg_index
```
for index definitions. For MySQL, query
```
information_schema.STATISTICS
```
for index details.

Map database column types to ORM field types:

```
varchar/text
```
->
```
String
```
/
```
@Column('text')
```
```
integer/bigint
```
->
```
Int
```
/
```
@Column('int')
```
```
boolean
```
->
```
Boolean
```
/
```
@Column('boolean')
```

timestamp/datetime

DateTime

@Column('timestamp')

```
jsonb/json
```
->
```
Json
```
/
```
@Column('jsonb')
```
```
uuid
```
->
```
String
```
with
```
@default(uuid())
```
or
```
uuid.uuid4
```
Custom enums -> Generate enum type definitions

Generate model classes with proper decorators/attributes:
- For Prisma: Generate
```
schema.prisma
```
  with
```
model
```
  blocks,
```
@id
```
  ,
```
@unique
```
  ,
```
@relation
```
  , and
```
@default
```
  directives.
- For TypeORM: Generate entity classes with
```
@Entity()
```
  ,
```
@Column()
```
  ,
```
@PrimaryGeneratedColumn()
```
  ,
```
@ManyToOne()
```
  ,
```
@OneToMany()
```
  decorators.
- For SQLAlchemy: Generate model classes extending
```
Base
```
  with
```
Column()
```
  ,
```
ForeignKey()
```
  ,
```
relationship()
```
  , and
```
__tablename__
```
  .
- For Drizzle: Generate table definitions with
```
pgTable()
```
  ,
```
serial()
```
  ,
```
varchar()
```
  ,
```
timestamp()
```
  , and
```
relations()
```
  .
Generate relationship mappings from foreign key constraints. Detect one-to-one (unique FK), one-to-many, and many-to-many (junction table with two FKs) patterns automatically. Add both sides of each relationship with proper cascade options.
Create migration files that capture the current schema state. For Prisma:
```
npx prisma migrate dev --name init
```
. For TypeORM: generate migration with
```
typeorm migration:generate
```
. For Alembic:
```
alembic revision --autogenerate
```
.
Generate repository/service layer with common CRUD operations:
```
findById
```
,
```
findAll
```
with pagination,
```
create
```
,
```
update
```
,
```
delete
```
, and relationship-aware queries (
```
findWithRelations
```
).
Add validation decorators or constraints matching database CHECK constraints and NOT NULL columns. Use
```
class-validator
```
for TypeORM, Pydantic validators for SQLAlchemy, or Zod schemas for Prisma.
Generate TypeScript/Python type definitions or interfaces for API layer consumption, ensuring the ORM models and API types stay synchronized.
Validate generated models by running a test migration against a temporary database or by comparing the generated schema against the live database schema with a diff tool.

Output

Model/entity files with full type annotations, decorators, and relationship mappings
Migration files capturing the initial schema state
Enum type definitions for database enum columns
Repository/service classes with typed CRUD operations
Validation schemas (Zod, class-validator, Pydantic) matching database constraints
Type definition files for API layer consumption

Error Handling

Error	Cause	Solution
Circular relationship dependency	Two entities reference each other, causing import cycles	Use lazy loading ( `() => RelatedEntity` ) in TypeORM; use `ForwardRef` in SQLAlchemy; split into separate files with deferred imports
Unknown column type mapping	Database uses custom types, extensions, or domain types not in the standard mapping	Add custom type mapping in generator config; use `@Column({ type: 'text' })` as fallback; register custom transformers
Migration conflicts with existing data	Generated migration adds NOT NULL columns without defaults	Add default values to new columns; create a two-phase migration (add nullable, backfill, set NOT NULL)
Junction table not detected as many-to-many	Junction table has extra columns beyond the two foreign keys	Model as an explicit entity with two ManyToOne relationships instead of an implicit ManyToMany
Schema drift between ORM models and database	Manual database changes not reflected in ORM code	Run introspection again; use `prisma db pull` or `sqlacodegen` to regenerate; diff against existing models

Examples

Prisma schema from PostgreSQL e-commerce database: Introspect 15 tables including users, orders, products, and categories. Generate

schema.prisma

with proper

@relation

directives, enum types for order status, and

@default(autoincrement())

for serial columns. Output includes Zod validation schemas for each model.

TypeORM entities from MySQL SaaS application: Generate entity classes for a multi-tenant application with tenant isolation. Each entity includes a

tenantId

column with a custom

@TenantAware

decorator. Repository layer includes tenant-scoped query methods.

SQLAlchemy models from legacy database with naming conventions: Introspect a database with inconsistent naming (mix of camelCase and snake_case). Generate models with

__tablename__

preserving original names while using Pythonic property names. Alembic migration captures the full schema.

Resources

Prisma introspection: https://www.prisma.io/docs/orm/prisma-schema/introspection
TypeORM entity documentation: https://typeorm.io/entities
SQLAlchemy ORM tutorial: https://docs.sqlalchemy.org/en/20/orm/
Drizzle ORM schema: https://orm.drizzle.team/docs/sql-schema-declaration
Django inspectdb command: https://docs.djangoproject.com/en/5.0/howto/legacy-databases/