Annotations

Kiln provides four annotations. All have SOURCE retention — they are consumed entirely at compile time and produce no runtime overhead.

Annotation	Target	Purpose
@DbEntity	Class	Marks a data class as a database table
@PrimaryKey	Property	Designates a primary key column — two or more form a composite key
@Column	Property	Overrides column name, adds constraints, hints migration
@Ignore	Property	Excludes a property from the schema
@Relation	Property	Marks a FK property; generates findBy<Parent>, observeBy<Parent>, deleteBy<Parent>

Minimal example

@DbEntity(tableName = "products")
data class Product(
    @PrimaryKey(autoGenerate = true) val id: Long = 0,  // (1)!
    val name: String,                                    // (2)!
    @Column(name = "price_cents") val price: Long,       // (3)!
    @Column(unique = true) val sku: String,              // (4)!
    @Ignore val displayPrice: String = ""                // (5)!
)

1. Auto-generated integer PK — pass id = 0 on insert, SQLite assigns the real id.
2. No @Column needed — property name is used as column name as-is.
3. @Column(name = …) overrides the column name in SQLite.
4. @Column(unique = true) adds a UNIQUE constraint.
5. @Ignore — not stored, not read back from the database.

What gets generated

For Product above, Kiln generates:

• ProductRepository — all CRUD, reactive, and DSL methods
• ProductColumns — typed Column<T> references for use in DSL queries:

val expensiveProducts = productRepo.findWhere {
    ProductColumns.price gt 10_000L
}