Prisma Skill
Provides type-safe database operations as an alternative to raw SQL. This codebase currently uses the pg library with raw SQL queries. Prisma offers automatic type generation, declarative schema modeling, and migration management - eliminating the manual row mapping and SQL injection risks present in raw SQL approaches.
Quick Start
Install and Initialize
bash
cd backend npm install prisma @prisma/client npx prisma init
Schema Definition
prisma
// prisma/schema.prisma
generator client {
provider = "prisma-client-js"
}
datasource db {
provider = "postgresql"
url = env("DATABASE_URL")
}
model Product {
id Int @id @default(autoincrement())
name String
shortDescription String @map("short_description")
description String
price Decimal @db.Decimal(10, 2)
salePrice Decimal? @map("sale_price") @db.Decimal(10, 2)
imageUrl String @map("image_url")
inventory Int @default(0)
categories Json
highlights Json?
usage String?
isNew Boolean @default(false) @map("is_new")
isFeatured Boolean @default(false) @map("is_featured")
salesCount Int @default(0) @map("sales_count")
createdAt DateTime @default(now()) @map("created_at")
updatedAt DateTime @updatedAt @map("updated_at")
translations ProductTranslation[]
orderItems OrderItem[]
variants ProductVariant[]
@@map("products")
}
model ProductTranslation {
id Int @id @default(autoincrement())
productId Int @map("product_id")
languageCode String @map("language_code") @db.VarChar(10)
name String @db.VarChar(255)
shortDescription String @map("short_description")
description String
highlights Json?
usage String?
slug String? @db.VarChar(255)
createdAt DateTime @default(now()) @map("created_at")
updatedAt DateTime @updatedAt @map("updated_at")
product Product @relation(fields: [productId], references: [id], onDelete: Cascade)
language Language @relation(fields: [languageCode], references: [code], onDelete: Cascade)
@@unique([productId, languageCode])
@@map("product_translations")
}
Client Usage
typescript
// backend/src/db/prisma.ts
import { PrismaClient } from '@prisma/client';
const prisma = new PrismaClient({
log: process.env.NODE_ENV === 'development' ? ['query', 'warn', 'error'] : ['error'],
});
export { prisma };
Key Concepts
| Concept | Usage | Example |
|---|---|---|
@map | Map field to snake_case column | @map("created_at") |
@@map | Map model to table name | @@map("products") |
| Relations | Define FK relationships | product Product @relation(...) |
@db.Decimal | Specify PostgreSQL types | @db.Decimal(10, 2) |
@@unique | Composite unique constraints | @@unique([productId, languageCode]) |
| Transactions | Atomic operations | prisma.$transaction([...]) |
Common Patterns
Fetching with Translation Fallback
When: Getting localized content with English fallback
typescript
const product = await prisma.product.findUnique({
where: { id: productId },
include: {
translations: {
where: { languageCode: lang },
},
},
});
// Apply translation or fallback to base
const name = product.translations[0]?.name ?? product.name;
Transactions for Orders
When: Creating orders with inventory updates
typescript
await prisma.$transaction(async (tx) => {
const order = await tx.order.create({ data: orderData });
for (const item of items) {
await tx.orderItem.create({
data: { orderId: order.id, ...item },
});
await tx.product.update({
where: { id: item.productId },
data: { inventory: { decrement: item.quantity } },
});
}
return order;
});
See Also
Related Skills
- •See the postgresql skill for raw SQL patterns and PostgreSQL-specific features
- •See the typescript skill for type inference patterns with Prisma
- •See the zod skill for runtime validation of Prisma inputs