Getting Started with Multiplatform

First apply the gradle plugin in your project.

KotlinGroovy

plugins {
  id("app.cash.sqldelight") version "2.0.0-rc02"
}

repositories {
  google()
  mavenCentral()
}

sqldelight {
  databases {
    create("Database") {
      packageName.set("com.example")
    }
  }
}

plugins {
  id "app.cash.sqldelight" version "2.0.0-rc02"
}

repositories {
  google()
  mavenCentral()
}

sqldelight {
  databases {
    Database { // This will be the name of the generated database class.
      packageName = "com.example"
    }
  }
}

Put your SQL statements in a .sq file under src/commonMain/sqldelight. Typically the first statement in the SQL file creates a table.

-- src/commonMain/sqldelight/com/example/sqldelight/hockey/data/Player.sq

CREATE TABLE hockeyPlayer (
  player_number INTEGER NOT NULL,
  full_name TEXT NOT NULL
);

CREATE INDEX hockeyPlayer_full_name ON hockeyPlayer(full_name);

INSERT INTO hockeyPlayer (player_number, full_name)
VALUES (15, 'Ryan Getzlaf');

From this, SQLDelight will generate a Database Kotlin class with an associated Schema object that can be used to create your database and run your statements on it. Generating the Database file happens during the 'generateSqlDelightInterface' gradle task. This task runs during the 'make project'/'make module' build task, or automatically if you have the SQLDelight IDE plugin.

Accessing the generated database also requires a driver, which SQLDelight provides implementations of:

KotlinGroovy

kotlin {
  // The drivers needed will change depending on what platforms you target:

  sourceSets.androidMain.dependencies {
    implementation("app.cash.sqldelight:android-driver:2.0.0-rc02")
  }

  // or sourceSets.iosMain, sourceSets.windowsMain, etc.
  sourceSets.nativeMain.dependencies {
    implementation("app.cash.sqldelight:native-driver:2.0.0-rc02")
  }

  sourceSets.jvmMain.dependencies {
    implementation("app.cash.sqldelight:sqlite-driver:2.0.0-rc02")
  }
}

kotlin {
  // The drivers needed will change depending on what platforms you target:

  sourceSets.androidMain.dependencies {
    implementation "app.cash.sqldelight:android-driver:2.0.0-rc02"
  }

  // or sourceSets.iosMain, sourceSets.windowsMain, etc.
  sourceSets.nativeMain.dependencies {
    implementation "app.cash.sqldelight:native-driver:2.0.0-rc02"
  }

  sourceSets.jvmMain.dependencies {
    implementation "app.cash.sqldelight:sqlite-driver:2.0.0-rc02"
  }
}

Creating Drivers

Create a factory class or method to obtain a SqlDriver instance in your common code.

src/commonMain/kotlin

import com.example.Database

expect class DriverFactory {
  fun createDriver(): SqlDriver
}

fun createDatabase(driverFactory: DriverFactory): Database {
  val driver = driverFactory.createDriver()
  val database = Database(driver)

  // Do more work with the database (see below).
}

Then implement this for each target platform:

src/androidMain/kotlinsrc/nativeMain/kotlinsrc/jvmMain/kotlin

actual class DriverFactory(private val context: Context) {
  actual fun createDriver(): SqlDriver {
    return AndroidSqliteDriver(Database.Schema, context, "test.db") 
  }
}

actual class DriverFactory {
  actual fun createDriver(): SqlDriver {
    return NativeSqliteDriver(Database.Schema, "test.db")
  }
}

actual class DriverFactory {
  actual fun createDriver(): SqlDriver {
    val driver: SqlDriver = JdbcSqliteDriver(JdbcSqliteDriver.IN_MEMORY)
    Database.Schema.create(driver)
    return driver
  }
}

For use with Kotlin/JS, see here.

Using Queries

SQL statements inside a .sq file can be labeled to have a typesafe function generated for them available at runtime.

selectAll:
SELECT *
FROM hockeyPlayer;

insert:
INSERT INTO hockeyPlayer(player_number, full_name)
VALUES (?, ?);

insertFullPlayerObject:
INSERT INTO hockeyPlayer(player_number, full_name)
VALUES ?;

Files with labeled statements in them will have a queries file generated from them that matches the .sq file name - putting the above sql into Player.sq generates PlayerQueries.kt. To get a reference to PlayerQueries you need to wrap the driver we made above:

// In reality the database and driver above should be created a single time
// and passed around using your favourite dependency injection/service
// locator/singleton pattern.
val database = Database(driver)

val playerQueries: PlayerQueries = database.playerQueries

println(playerQueries.selectAll().executeAsList())
// Prints [HockeyPlayer(15, "Ryan Getzlaf")]

playerQueries.insert(player_number = 10, full_name = "Corey Perry")
println(playerQueries.selectAll().executeAsList())
// Prints [HockeyPlayer(15, "Ryan Getzlaf"), HockeyPlayer(10, "Corey Perry")]

val player = HockeyPlayer(10, "Ronald McDonald")
playerQueries.insertFullPlayerObject(player)

And that's it! Check out the other pages on the sidebar for other functionality.