prisma-queries

What this skill does

# Prisma Queries

Query and mutate data using Prisma Client with type-safe operations.

## Client Setup

```typescript
import { PrismaClient } from '@prisma/client'

const prisma = new PrismaClient()

// With logging
const prisma = new PrismaClient({
  log: ['query', 'info', 'warn', 'error'],
})
```

## CRUD Operations

### Create

```typescript
// Create single record
const user = await prisma.user.create({
  data: {
    email: '[email protected]',
    name: 'Alice',
  },
})

// Create many
const count = await prisma.user.createMany({
  data: [
    { email: '[email protected]' },
    { email: '[email protected]' },
  ],
  skipDuplicates: true,
})
```

### Read

```typescript
// Find unique (by unique field)
const user = await prisma.user.findUnique({
  where: { email: '[email protected]' },
})

// Find first matching
const user = await prisma.user.findFirst({
  where: { name: { contains: 'Alice' } },
})

// Find many
const users = await prisma.user.findMany({
  where: { role: 'ADMIN' },
  orderBy: { createdAt: 'desc' },
  take: 10,
  skip: 0,
})

// Find or throw
const user = await prisma.user.findUniqueOrThrow({
  where: { id: 1 },
})
```

### Update

```typescript
// Update single
const user = await prisma.user.update({
  where: { id: 1 },
  data: { name: 'New Name' },
})

// Upsert (update or create)
const user = await prisma.user.upsert({
  where: { email: '[email protected]' },
  update: { name: 'Alice Updated' },
  create: { email: '[email protected]', name: 'Alice' },
})
```

### Delete

```typescript
// Delete single
const user = await prisma.user.delete({
  where: { id: 1 },
})

// Delete many
const count = await prisma.user.deleteMany({
  where: { verified: false },
})
```

## Filtering

### Basic Filters

```typescript
const users = await prisma.user.findMany({
  where: {
    email: '[email protected]',        // Exact match
    name: { contains: 'Ali' },         // Contains
    age: { gte: 18 },                  // Greater than or equal
    role: { in: ['ADMIN', 'MOD'] },    // In list
    verified: { not: false },          // Not equal
  },
})
```

### Filter Operators

| Operator | Description |
|----------|-------------|
| `equals` | Exact match |
| `not` | Not equal |
| `in` | In array |
| `notIn` | Not in array |
| `lt`, `lte` | Less than (or equal) |
| `gt`, `gte` | Greater than (or equal) |
| `contains` | String contains |
| `startsWith` | String starts with |
| `endsWith` | String ends with |
| `mode: 'insensitive'` | Case-insensitive |

## Select and Include

### Select Specific Fields

```typescript
const users = await prisma.user.findMany({
  select: {
    id: true,
    email: true,
    // Only these fields returned
  },
})
```

### Include Relations

```typescript
const user = await prisma.user.findUnique({
  where: { id: 1 },
  include: {
    posts: true,            // All posts
    profile: true,          // Profile relation
  },
})
```

## Pagination

```typescript
// Offset pagination
const users = await prisma.user.findMany({
  skip: 20,
  take: 10,
  orderBy: { createdAt: 'desc' },
})

// Cursor pagination
const users = await prisma.user.findMany({
  take: 10,
  cursor: { id: lastUserId },
  orderBy: { id: 'asc' },
})
```

## Advanced Operations

For complex query patterns beyond basic CRUD, see [references/advanced-queries.md](references/advanced-queries.md):

| Topic | Use When |
|-------|----------|
| Combining Filters | Building complex AND/OR/NOT conditions |
| Relation Filters | Filtering by related record properties |
| Nested Includes | Loading deeply nested or filtered relations |
| Aggregations | count, sum, avg, min, max, groupBy |
| Transactions | Multi-operation atomicity (sequential or interactive) |
| Nested Writes | Creating/updating related records in one call |
| Raw Queries | Complex SQL the Prisma Client can't express |

## Best Practices

1. **Use `select` to limit fields** - Reduce payload size
2. **Paginate large results** - Use `take` and `skip`/`cursor`
3. **Use transactions for consistency** - Multiple related operations
4. **Handle errors gracefully** - Catch Prisma errors by code
5. **Disconnect on shutdown** - Call `prisma.$disconnect()`

## Reference Files

| File | Contents |
|------|----------|
| [references/advanced-queries.md](references/advanced-queries.md) | Combining filters, relation filters, nested includes, aggregations, transactions, nested writes, raw queries |