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我想用 async/await 运行多个函数，包括一个 for 循环。循环也需要彼此运行完成。目前我正在使用这个功能，似乎它不能正常工作。

对于 for 循环查询，我需要在第一个查询中创建的 id 来执行它。

const createStudent = async (studentObj) => {
    try {
        await database.action(async () => {
            const newStudent = await studentCollection.create(student => {
                student.name = studentObj.name
                student.age = studentObj.age
            })

            for (let contactObj of studentObj.contacts) {
                try {
                    await contactCollections.create(contact => {
                        contact.student_id = newStudent.id
                        contact.type = contactObj.type
                        contact.contact = contactObj.contact
                    })
                } catch (error) {
                    console.log(error);
                }
            }
        })
    } catch (error) {
        console.log(error);
    }
}

目前我遇到了一个错误

[WatermelonDB] The action you're trying to perform (unnamed) can't be performed yet, because there are 2 actions in the queue. 
Current action: unnamed. Ignore this message if everything is working fine. 
But if your actions are not running, it's because the current action is stuck. 
Remember that if you're calling an action from an action, you must use subAction(). See docs for more details.
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1 回答 1

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是的你是对的！。它不能与多个数据库一起创建记录请求正常工作。

每当您在一个操作中进行多个更改（创建、删除或更新记录）时，您应该对它们进行批处理。

见：https ://nozbe.github.io/WatermelonDB/Actions.html

你可以这样做：

const batchActions = [];

for (let contactObj of studentObj.contacts) {
  batchActions.push(
    contactCollections.prepareCreate(contact => {
      contact.student_id = newStudent.id
      contact.type = contactObj.type
      contact.contact = contactObj.contact
    })
  )
}

database.batch(batchActions)

希望这能解决你的问题

于 2020-11-08T17:08:08.620 回答