Types

SQLite Types

SQLDelight column definitions are identical to regular SQLite column definitions but support an extra column constraint which specifies the Kotlin type of the column in the generated interface.

CREATE TABLE some_types (
  some_long INTEGER,           -- Stored as INTEGER in db, retrieved as Long
  some_double REAL,            -- Stored as REAL in db, retrieved as Double
  some_string TEXT,            -- Stored as TEXT in db, retrieved as String
  some_blob BLOB               -- Stored as BLOB in db, retrieved as ByteArray
);

Primitives

A sibling module that adapts primitives for your convenience.

KotlinGroovy

dependencies {
  implementation("app.cash.sqldelight:primitive-adapters:2.1.0-SNAPSHOT")
}

dependencies {
  implementation "app.cash.sqldelight:primitive-adapters:2.1.0-SNAPSHOT"
}

The following adapters exist:

• FloatColumnAdapter — Retrieves kotlin.Float for an SQL type implicitly stored as kotlin.Double
• IntColumnAdapter — Retrieves kotlin.Int for an SQL type implicitly stored as kotlin.Long
• ShortColumnAdapter — Retrieves kotlin.Short for an SQL type implicitly stored as kotlin.Long

Custom Column Types

If you'd like to retrieve columns as custom types you can specify a Kotlin type:

import kotlin.String;
import kotlin.collections.List;

CREATE TABLE hockeyPlayer (
  cup_wins TEXT AS List<String> NOT NULL
);

However, creating the Database will require you to provide a ColumnAdapter which knows how to map between the database type and your custom type:

val listOfStringsAdapter = object : ColumnAdapter<List<String>, String> {
  override fun decode(databaseValue: String) =
    if (databaseValue.isEmpty()) {
      listOf()
    } else {
      databaseValue.split(",")
    }
  override fun encode(value: List<String>) = value.joinToString(separator = ",")
}

val queryWrapper: Database = Database(
  driver = driver,
  hockeyPlayerAdapter = hockeyPlayer.Adapter(
    cup_winsAdapter = listOfStringsAdapter
  )
)

Enums

As a convenience the SQLDelight runtime includes a ColumnAdapter for storing an enum as String data.

import com.example.hockey.HockeyPlayer;

CREATE TABLE hockeyPlayer (
  position TEXT AS HockeyPlayer.Position
)

val queryWrapper: Database = Database(
  driver = driver,
  hockeyPlayerAdapter = HockeyPlayer.Adapter(
    positionAdapter = EnumColumnAdapter()
  )
)

Value types

SQLDelight can generate a value type for a column which wraps the underlying database type if requested:

CREATE TABLE hockeyPlayer (
  id INT AS VALUE
);