Usage Docs

DBFlow is a Kotlin SQLite library for Android that makes it ridiculously easy to interact and use databases. Built with Annotation Processing, code use within a DB is fast, efficient, and type-safe. It removes the tedious (and tough-to-maintain) database interaction code, while providing a very SQLite-like query syntax.

Creating a database is as easy as a few lines of code:

@Database(version = 1)
abstract class AppDatabase: DBFlowDatabase

The @Database annotation generates a DatabaseDefinition which now references your SQLite Database on disk in the file named "AppDatabase.db". You can reference it in code as:

val db = database<AppDatabase>();

// or
database<AppDatabase> { db ->


To ensure generated code in DBFlow is found by the library, initialize the library in your Application class:

class MyApp : Application {

  override fun onCreate() {

By default, DBFlow generates the GeneratedDatabaseHolder class, which is instantiated once by reflection, only once in memory.

Creating a table is also very simple:

@Table(database = AppDatabase::class, name = "User2")
class User(@PrimaryKey var id: Int = 0,
           var firstName: String? = null,
           var lastName: String? = null,
           var email: String? = null)

Then to create, read, update, and delete the model:

// always utilize DB transactions when possible.
databaseForTable<User>().executeTransaction { db ->
  val user = User(id = UUID.randomUUID(),
                name = "Andrew Grosner",
                age = 27)
  user.insert(db) = "Not Andrew Grosner";


// find adult users synchronously
val users = (select from User::class
               where (User_Table.age greaterThan 18))

// or asynchronous retrieval (preferred)
(select from User::class where User_Table.age.greaterThan(18))
 .async(database<AppDatabase>()) { queryList(it) }
  success = { transaction, result ->
   // use result here
  error = { transaction, error ->
  // handle any errors

// use coroutines! or RX3 or LiveData
async {
   val result = (delete<SimpleModel>() where"5"))
    .awaitTransact(db) { executeUpdateDelete(database) }

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