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Entity Definitions

Three annotated data classes — this is all the schema code you write.

Entities.kt
@DbEntity(tableName = "projects")
data class Project(
    @PrimaryKey(autoGenerate = true) val id: Long = 0,
    val name: String,
    val description: String = "",
    @Column(name = "hex_color") val color: String = "#4CAF50",
    @Column(name = "is_archived", index = true) val isArchived: Boolean = false,
    @Column(name = "created_at") val createdAt: String = ""
)

@DbEntity(tableName = "tasks")
data class Task(
    @PrimaryKey(autoGenerate = true) val id: Long = 0,
    @Column(name = "project_id", index = true) val projectId: Long,  // (1)!
    val title: String,
    val notes: String = "",
    val priority: Int = 1,        // 1 = low  2 = medium  3 = high
    val status: String = "TODO",  // TODO | IN_PROGRESS | DONE
    @Column(name = "is_completed") val isCompleted: Boolean = false,
    @Column(name = "due_date") val dueDate: String = ""
)

@DbEntity(tableName = "checklist_items")
data class ChecklistItem(
    @PrimaryKey(autoGenerate = true) val id: Long = 0,
    @Column(name = "task_id", index = true) val taskId: Long,  // (1)!
    val text: String,
    @Column(name = "is_done") val isDone: Boolean = false
)
  1. index = true on foreign key columns generates CREATE INDEX — makes findWhere { TaskColumns.projectId eq id } fast without a full table scan.

Design notes

Indexes on FK columns — project_id and task_id both have index = true. Without indexes, every findWhere on these columns performs a full table scan. With indexes, lookups are O(log n).

Dates as String — created_at and due_date are stored as ISO-8601 strings (e.g. "2024-09-15T10:30:00Z"). This keeps the schema portable and avoids type-change migrations when date handling changes.

Status as String — TODO | IN_PROGRESS | DONE is stored as plain text. You validate the set of valid values in your UI or domain layer, not in the schema.

All fields have defaults — this makes copy() ergonomic for partial updates:

// Update only the status — all other fields unchanged
taskRepo.update(task.copy(status = "IN_PROGRESS"))

Generated output

After a build, Kiln generates:

  • ProjectRepository + ProjectColumns
  • TaskRepository + TaskColumns
  • ChecklistItemRepository + ChecklistItemColumns