advanced

Advanced Example - Custom Types & Prepared Queries

This example demonstrates db-catalyst's unique features that sqlc doesn't have.

Features Demonstrated

• Custom Types with Pointer Control - Map SQLite types to custom Go types
• Schema Transformation - Use domain types in SQL, get Go types in code
• Prepared Queries - Pre-compiled statements with metrics
• Type Safety - Strongly typed IDs and enums

Custom Types

// Your domain types
type UserID int64
type Status string
type Money int64 // stored as cents

Map them in config:

[[custom_types.mapping]]
custom_type = "user_id"
sqlite_type = "INTEGER"
go_type = "github.com/electwix/db-catalyst/examples/advanced/types.UserID"
pointer = false

Running

cd examples/advanced
db-catalyst
go run main.go

What Makes This Special

1. Type Safety: Can't accidentally pass a ProductID where UserID expected
2. Pointer Control: Explicit pointer = true/false regardless of nullability
3. Prepared Statements: Metrics and thread-safe initialization
4. Schema Stays Clean: Use custom types in SQL, they transform automatically