1. Moleculer 目前支持SQLite，MySQL，MariaDB，PostgreSQL，MSSQL等数据库，这里以mysql为例

2. package.json 增加mysql依赖

"mysql2": "^2.3.3",
"sequelize": "^6.21.3",
"moleculer-db-adapter-sequelize": "^0.2.15",
"moleculer-db": "^0.8.24",

npm install moleculer-db-adapter-sequelize sequelize --save
npm install moleculer-db --save

 3.然后执行对应数据库的命令

SQLite
 npm install sqlite3 --save

# For MySQL
npm install mysql2 --save

# For MariaDB
npm install mariadb --save

# For PostgreSQL
 npm install pg pg-hstore --save

# For MSSQL
$npm install tedious --save

4.服务增加如下操作：

const { ServiceBroker } = require("moleculer");
const DbService = require("moleculer-db");
const SqlAdapter = require("moleculer-db-adapter-sequelize");
const Sequelize = require("sequelize");
const broker = new ServiceBroker();
/**
 * @typedef {import('moleculer').ServiceSchema} ServiceSchema Moleculer's Service Schema
 * @typedef {import('moleculer').Context} Context Moleculer's Context
 */

broker.createService({
	name: "products",
	mixins: [DbService],
	adapter: new SqlAdapter('test', 'root', 'root', {
		host: 'localhost',
		dialect: 'mysql' ,
		pool: {
			max: 5,
			min: 0,
			idle: 10000
		}
	}),
	model: {
		name: "products",
		define: {
			title: Sequelize.STRING,
			content: Sequelize.TEXT,
			votes: Sequelize.INTEGER,
			author: Sequelize.INTEGER,
			status: Sequelize.BOOLEAN
		},
		options: {

		}
	},
});


broker.start()
	// Create a new post
	.then(() => broker.call("products.create", {
		title: "My first post",
		content: "Lorem ipsum...",
		votes: 0
	}))
	.then(() => broker.call("products.find").then(console.log));

5.启动项目： 数据库自动创表products,并插入了一条数据，可以查询出来

6.具体的crud 可以参考Sequelize | Feature-rich ORM for modern TypeScript & JavaScript 实现，这里就不详细介绍了