Firebird SQL Client Library for Kotlin Multiplatform

This is a Kotlin Multiplatform project for working with a Firebird SQL database.

Don't know Firebird? I recommend reading Firebird 5 Quick Start Guide, for a step-by-step introduction.

Supported systems are JVM, Android and Kotlin Native.

Firebird 5 is the version targeted in this library, it should work with earlier versions but this has not been tested.

Organization

The project is organized into three modules,

native: The JNI library
library: The main kotlin library
library-ext: An extension to the main module containing the following dependencies:
- kotlinx-datetime
- kotlin-multiplatform-bignum

Integration

JVM & Kotlin Native

repositories {
    mavenCentral()
}

dependencies {
   // the main dependency
   implementation("com.progdigy:FirebirdClient:1.0")
   
   // or the extended dependency 
   implementation("com.progdigy:FirebirdClient-ext:1.0")
}

Android

Download Firebird 5 Android Embedded and put it in the "libs" folder at the root of your module.

⚠️ There is an issue with Android 14 that has been fixed but is not yet officially available, you need to use the snapshots.

Then declare these dependencies in your gradle file

repositories {
    mavenCentral()
}

dependencies {
   implementation(files("libs/Firebird-5.0.0.xxxx-x-android-embedded.aar"))
   implementation("com.progdigy:FirebirdClient:1.0")
    
}

Initialize the Firebird library configuration. This extracts the necessary configuration files into the "firebird" subfolder of your application's storage space and tells Firebird where to find them.

override fun onCreate(savedInstanceState: Bundle?) {
   super.onCreate(savedInstanceState)
   FirebirdConf.extractAssets(baseContext, false)
   FirebirdConf.setEnv(baseContext)

Use cases

Onboarding

This example creates a local database in embedded mode, the default encoding is UTF8 and dialect 3 is recommended for a new database.

fun attachment(block: Attachment.() -> Unit) { 
    val database = File("/tmp/database.fdb")
    if (!database.exists()) {
        Attachment.createDatabase(database.absolutePath, makeDPB {
            setDBCharset("UTF8")
            sqlDialect(3)
        }).use {
            it.transaction {
                execute("CREATE TABLE CUSTOMER (id int, name varchar(255))")
                execute("CREATE GENERATOR GEN_CUSTOMER")

                commitRetaining()

                statement("INSERT INTO CUSTOMER (id, name) VALUES (gen_id(GEN_CUSTOMER, 1), ?)") {
                    listOf("Terry Bull", "Jack Pott", "Anna Conda").forEach { name ->
                        params.setString(0, name)
                        execute()
                    }
                }
            }
            it.block()
        }
    } else
        Attachment.attachDatabase(database.absolutePath).use(block)
}

fun main() {
    attachment {
        statement("select id, name from CUSTOMER") {
            forEach {
                val id = getInt(0)
                val name = getString(1)
                println("id: $id, name: $name")
            }
        }
    }
}

Remote host

It is possible to connect to a remote database, please refer to the relevant documentation.

Attachment.attachDatabase("localhost:employee", makeDPB {
    userName("SYSDBA")
    password("masterkey")
})

Open

statement("select id, name from CUSTOMER") {
    open {
        while (!eof) {
            val id = getInt(0)
            val name = getString(1)
            println("id: $id, name: $name")
            fetch()
        }
    }
}

Execute

statement("INSERT INTO CUSTOMER (id, name) VALUES (gen_id(GEN_CUSTOMER, 1), ?)") {
    params.setString(0, "Barry Cade")
    execute()
}

Returning

statement("INSERT INTO CUSTOMER (id, name) VALUES (gen_id(GEN_CUSTOMER, 1), ?) RETURNING ID") {
    params.setString(0, "Ella Vader")
    execute()
    val id = result.getInt(0)
    println("id: $id")
}

Transaction

If you need to run several SQL queries that must be executed atomically, group them together in a single transaction.

transaction {

}

You may need to validate or cancel certain changes without leaving the transaction.

transaction {
  commitRetaining()
  rollbackRetaining()
}

Transactions can be configured in a number of ways.

transaction(makeTPB {
    write()
    readCommitted()
    noWait()
    recVersion()
}) {

}

Select for update

transaction {
    statement("SELECT * FROM CUSTOMER FOR UPDATE", "S") {
        open {
            statement("UPDATE CUSTOMER SET NAME = ? WHERE CURRENT OF S") {
                while (!eof) {
                    params.setString(0, "John Doe")
                    execute()
                    fetch()
                }
            } 
        }
    }
}

hgourvest/Firebird-Client-KMP