In this quickstart, you will create and deploy a small sample database and access it from an Android app.
Prerequisites
To complete this quickstart, you'll need the following:
- An environment with the following tools installed:
- A recent version of Android Studio .
- The Firebase CLI
. If you have NPM installed, run:
npm install -g firebase-tools@latest
- A Google Account.
Tutorial
1. Create a new Android Studio project
In Android Studio, create a new project with the Empty Activity template.
Name the project Quickstart App with the package name com.example.quickstartapp .
2. Add Firebase to your Android Studio project
Add the Firebase dependencies and the Kotlin serialization plugin to your build.gradle.kts
files.
plugins { alias ( libs . plugins . android . application ) apply false alias ( libs . plugins . kotlin . compose ) apply false // Add this line. id ( "com.google.gms.google-services" ) version "4.4.4" apply false }
plugins { alias ( libs . plugins . android . application ) alias ( libs . plugins . kotlin . compose ) // Add these lines. kotlin ( "plugin.serialization" ) version libs . versions . kotlin id ( "com.google.gms.google-services" ) } // ... dependencies { // ... // Add these lines. implementation ( "org.jetbrains.kotlinx:kotlinx-coroutines-android:1.11.0" ) implementation ( "org.jetbrains.kotlinx:kotlinx-serialization-core:1.11.0" ) implementation ( platform ( "com.google.firebase:firebase-bom:34.14.1" )) implementation ( "com.google.firebase:firebase-dataconnect" ) }
3. Initialize a Firebase project
Change to the Android Studio project directory and initialize a Firebase project in it.
cd ~/QuickstartApp
firebase login --reauth
firebase init dataconnect
When prompted, choose the following options:
- Create a new Firebase project.
- Don't create a schema with Gemini (in this tutorial, you'll use a pre-built example schema).
- Provision a free trial Cloud SQL instance and database.
Accept the default values for all other prompts.
Next, register your Android app in your Firebase project.
firebase apps:create -a com.example.quickstartapp android android-quickstart
firebase apps:sdkconfig android -o app/google-services.json
4. Review the example GraphQL definitions
In SQL Connect , you define all of your database schemas and operations using GraphQL. When you initialized your project, the Firebase CLI created some example definitions to get you started.
type Movie @ table { title : String ! imageUrl : String ! genre : String } type MovieMetadata @ table { movie : Movie ! @ unique rating : Float releaseYear : Int description : String }
query ListMovies @auth ( level : PUBLIC ) { movies { id title imageUrl genre } }
5. Deploy your schemas and operations
Whenever you make changes to your database schemas, queries, or mutations, you must deploy them for your changes to take effect on the database.
firebase deploy --only dataconnect
6. Seed the database with sample data
This seed data will give you something to look at when you test the sample app. Note that in this step you are executing arbitrary GraphQL, which is allowed for administrative tasks.
firebase dataconnect:execute dataconnect/seed_data.gql
7. Generate an Android client SDK
This command uses your GraphQL definitions to generate an Android client SDK specifically for your database. You use this library in your client app to perform all database operations.
You can generate libraries for multiple platforms, including
Swift for iOS, JavaScript for web, and Flutter, by adding definitions to connector.yaml
.
firebase dataconnect:sdk:generate
public interface ExampleConnector : GeneratedConnector<ExampleConnector> { override val dataConnect : com . google . firebase . dataconnect . FirebaseDataConnect public val listMovies : ListMoviesQuery // ... }
8. Write a sample Android client
Replace the contents of app/src/main/java/com/example/quickstartapp/MainActivity.kt
with this simple
Android app.
Notice that the app completes the necessary database access using a function from the generated SDK.
package com.example.quickstartapp import android.os.Bundle import androidx.activity.ComponentActivity import androidx.activity.compose.setContent import androidx.activity.enableEdgeToEdge import androidx.compose.foundation.layout.fillMaxSize import androidx.compose.foundation.layout.padding import androidx.compose.foundation.lazy.LazyColumn import androidx.compose.foundation.lazy.items import androidx.compose.material3.Scaffold import androidx.compose.material3.Text import androidx.compose.runtime.LaunchedEffect import androidx.compose.runtime.getValue import androidx.compose.runtime.mutableStateOf import androidx.compose.runtime.remember import androidx.compose.runtime.setValue import androidx.compose.ui.Modifier import com.example.quickstartapp.ui.theme.QuickstartAppTheme import com.google.firebase.dataconnect.generated.ExampleConnector import com.google.firebase.dataconnect.generated.ListMoviesQuery import com.google.firebase.dataconnect.generated.execute import com.google.firebase.dataconnect.generated.instance class MainActivity : ComponentActivity () { override fun onCreate ( savedInstanceState : Bundle?) { super . onCreate ( savedInstanceState ) enableEdgeToEdge () setContent { QuickstartAppTheme () { Scaffold ( modifier = Modifier . fillMaxSize ()) { innerPadding - > var movies by remember { mutableStateOf ( emptyList<ListMoviesQuery . Data . MoviesItem > ()) } LaunchedEffect ( Unit ) { // Queries need to be executed in a coroutine context try { movies = ExampleConnector . instance . listMovies . execute (). data . movies } catch ( e : Exception ) { // TODO: Handle error, e.g., show a Toast or update a state variable to // display an error message. } } LazyColumn ( modifier = Modifier . padding ( innerPadding )) { items ( movies ) { movie - > Text ( text = movie . title ) } } } } } } }
9. Try the app
From Android Studio, run the example app to see it in action.
Next steps
Try the SQL Connect VS Code extension
When developing with SQL Connect , we strongly recommend using the SQL Connect VS Code extension . Even if you don't use Visual Studio Code as your primary development environment, the extension provides several features that make schema and operation development more convenient:
- A GraphQL language server, providing syntax checking and autocomplete suggestions specific to SQL Connect
- CodeLens buttons in line with your code that let you read and write data from your schema definition files and execute queries and mutations from your operation definitions.
- Automatically keep your generated SDKs synchronized with your GraphQL definitions.
- Simplified local emulator setup.
- Simplified deployment to production.
Use the SQL Connect emulator for local development
Although this tutorial showed you how to deploy SQL Connect schemas and operations directly to production, you will likely not want to make changes to your production database while you are actively developing your app. Instead, set up the SQL Connect emulator and do your development work against it rather than production. The emulator sets up a local PGlite instance that behaves similarly to a live PostgreSQL instance on Cloud SQL .
Learn how to write schemas and operations for your app
When developing apps with SQL Connect , the design of your schemas and operations is one of the first and most important development tasks you will complete.
- Gemini in the Firebase console is an AI tool that can generate SQL Connect schemas from a natural language description of your app. This tool can get you started very quickly, especially if you've never worked with relational databases before.
- Alternatively, you can write database schemas, queries, and mutations directly using GraphQL. Start with the guidance in Design SQL Connect schemas , and then continue to the follow-up pages to learn how to write operations.
