Using Apache Ignite from a MoonBit Agent

The MoonBit SDK already includes the generated package for golem:rdbms/ignite2@1.5.0.

Add the Package Import

In the component’s moon.pkg, add an alias for the package:


import {
  "golemcloud/golem_sdk/interface/golem/rdbms/ignite2" @ignite,
}

Open a Connection

Ignite uses thin-client URLs like ignite://host:10800.


let conn = @ignite.DbConnection::open("ignite://127.0.0.1:10800")
  .or_error!("failed to connect to Ignite")

Query Data

Ignite placeholders use ?.


let result = conn.query(
  "SELECT ?",
  [@ignite.DbValue::DbString("hello")],
).or_error!("query failed")
 
let row = result.rows[0]
let value = row.values[0]
 
let message = match value {
  @ignite.DbValue::DbString(value) => value
  _ => abort("unexpected Ignite value")
}

Execute Statements


conn.execute(
  #|CREATE TABLE IF NOT EXISTS notes (
  #|  id INT PRIMARY KEY,
  #|  body VARCHAR
  #|) WITH "CACHE_NAME=notes"
  ,
  [],
).or_error!("create table failed")

Include WITH "CACHE_NAME=..." when creating tables through Ignite SQL.

Transactions


let tx = conn.begin_transaction().or_error!("failed to start transaction")
tx.execute(
  "INSERT INTO notes (id, body) VALUES (?, ?)",
  [@ignite.DbValue::DbInt(1), @ignite.DbValue::DbString("hello")],
).or_error!("insert failed")
tx.commit().or_error!("commit failed")