如何在Grails中访问两个数据库

dependencies {
    runtimeOnly 'mysql:mysql-connector-java'
    runtimeOnly 'org.postgresql:postgresql'
}

dataSource:
    pooled: true
    jmxExport: true
    driverClassName: com.mysql.jdbc.Driver
    username: sa
    password:
    dbCreate: update
    url: jdbc:mysql://localhost:3306/db1?useUnicode=yes&characterEncoding=UTF-8

dataSource_db2:
    pooled: true
    jmxExport: true
    driverClassName: org.postgresql.Driver
    username: sa
    password:
    dbCreate: update
    url: jdbc:postgresql://localhost:5432/db2

@Transactional(dataSource = 'dataSource')
class PersonDao {
    // ...
}

@Transactional(dataSource = 'dataSource_db2')
class ProductDao {
    // ...
}

class SomeController {
    def personDao
    def productDao

    def index() {
        def people = personDao.list()
        def products = productDao.list()

        [people: people, products: products]
    }
}