房间无异常错误。错误：不确定如何处理查询方法的返回类型答案

【问题标题】：Room unexcepted error. Error: Not sure how to handle query method's return type房间无异常错误。错误：不确定如何处理查询方法的返回类型
【发布时间】：2022-01-02 15:24:36
【问题描述】：

错误：不确定如何处理查询方法的返回类型重建项目后 DbDao 类中出现异常错误。在那之前，一切都很好，在那个类中没有做任何事情，也没有做任何与那个库有关的事情，但是突然之间它开始在生成的 java 文件中抛出错误

错误： D:\workspace\workspace\Android studio\CorralApp\ProjectCoral\app\build\tmp\kapt3\stubs\debug\com\mmscode\coralproject\db\DbDao.java:21：错误：不确定如何处理查询方法的返回类型（java.lang.Object）。 DELETE 查询方法必须返回 void 或 int（删除的行数）。公共抽象 java.lang.Object deleteUser(@org.jetbrains.annotations.NotNull() ^

例如，如果我删除函数 deleteUser，此错误将显示在其他函数上

代码：

    package com.mmscode.coralproject.db

import androidx.lifecycle.LiveData
import androidx.room.*


@Dao
abstract class DbDao {
    @Insert(onConflict = OnConflictStrategy.REPLACE)
    abstract suspend fun insertUserData(user: DbUser)

    @Query("DELETE FROM DbUser")
    abstract suspend fun deleteUser()

    @Query("SELECT * FROM DbUser")
    abstract suspend fun getUser(): DbUser?

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    abstract suspend fun insertDailySchedule(list: List<DbSchedule>)

    @Query("SELECT * FROM DbSchedule  where  scheduleStatusName NOT LIKE 'ENDED' ORDER BY eventTime")
    abstract fun getDailySchedule(): LiveData<List<DbSchedule>>?

    @Query("SELECT  * FROM DbSchedule where scheduleStatusName NOT LIKE 'ENDED'  AND date(substr(dateFrom,7,4)|| '-' ||substr(dateFrom,1,2)|| '-'||substr(dateFrom,4,2))  > date(:date,'start of month', '-1 month', '-10 day')")
    abstract suspend fun getDailySchedule2(date: String): List<DbSchedule>

    @Query("SELECT  * FROM DbSchedule where scheduleStatusName NOT LIKE 'ENDED'  ORDER BY eventTime")
    abstract suspend fun getDailySchedule3(): List<DbSchedule>

    @Query("SELECT  * FROM DbSchedule where scheduleStatusName NOT LIKE 'ENDED' and date(substr(dateFrom,7,4)|| '-' ||substr(dateFrom,1,2)|| '-'||substr(dateFrom,4,2)) between DATE(:dateFrom) AND DATE(:dateTo) ORDER BY eventTime")
    abstract suspend fun getSchedules(dateFrom: String, dateTo: String): List<DbSchedule>

    @Query("SELECT statusId from DbSchedule WHERE careId = :careId")
    abstract suspend fun getStatusId(careId: Int): Int

    @Query("UPDATE DbSchedule SET scheduleStatusName = :scheduleStatusName WHERE scheduleId = :scheduleId")
    abstract suspend fun updateReminder(scheduleId: Int, scheduleStatusName: String)

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    abstract suspend fun insertBreeds(list: List<DbBreeds>)

    @Query("SELECT * FROM DbBreeds where speciesname = :speciesName ORDER BY breedname")
    abstract suspend fun getBreeds(speciesName: String?): List<DbBreeds>?

    @Query("SELECT speciesname FROM DbBreeds GROUP BY speciesname ORDER BY speciesname")
    abstract  fun getSpecies(): LiveData<List<String>>?

    @Query("SELECT * FROM DbCareProviders WHERE category_name = :category  and valid = 'Y'")
    abstract suspend fun getProviders(category: String?): List<DbCareProviders>

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    abstract suspend fun insertProviders(list: List<DbCareProviders>)

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    abstract suspend fun insertNotifications(list: List<DBNotifications>)

    @Query("SELECT * FROM DBNotifications order by receive_date desc")
    abstract suspend fun getAllNotifications(): List<DBNotifications>

    @Query("SELECT COUNT(*) from DBNotifications WHERE upper(message_status_name) = 'UNREAD'")
    abstract suspend fun getCountUnreadNotifications(): Int


    @Query("UPDATE DBNotifications SET message_status_name='OPEN_NOT_READ' where message_status_name = 'UNREAD'")
    abstract suspend fun readNotifications()

    @Query("UPDATE DBNotifications SET message_status_name='READ' WHERE notification_id=:id")
    abstract suspend fun openNotification(id: Int)
    @Query("UPDATE DBNotifications SET message_status_name='READ'")
    abstract suspend fun openAllNotification()

    @Query("UPDATE DBNotifications SET member_status_name='ACTIVE' WHERE notification_id=:id")
    abstract suspend fun acceptFriendRequest(id: Int)

    @Query("UPDATE DBNotifications SET member_status_name='INACTIVE' WHERE notification_id=:id")
    abstract suspend fun ignoreFirenRequest(id: Int)

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    abstract suspend fun insertCareActivities(list: List<DBCareActivities>)

    @Query("SELECT * FROM DBCareActivities")
    abstract suspend fun getCareActivities(): List<DBCareActivities>

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    abstract suspend fun insertUserAccounts(list: List<DbUserAccounts>)

  /*  @Update(entity = DBNotifications::class)
    abstract fun ReadNotifications(notifications: List<DBNotifications> )*/

}

编辑：最后一个房间版本 2.3.0

 // Room
implementation "androidx.room:room-runtime:2.3.0"
kapt "androidx.room:room-compiler:2.3.0"
// Room ktx
implementation 'androidx.room:room-ktx:2.3.0'

【问题讨论】：

我会尝试清除缓存并使缓存失效
我试过了，但没有帮助....
我看到您正在使用协程，但我没有在您的依赖项中明确看到它。如果您添加implementation "androidx.room:room-coroutines:${versions.room}"，它会起作用吗？在发表此评论时，最新版本是2.1.0-alpha04
找不到 androidx.room:room-ktx:2.1.0-alpha04。和 androidx.room:room-coroutines 的相同错误

标签： java android kotlin android-room android-livedata

【解决方案1】：

请检查您的 kotlin 版本。
Kotlin 1.6.0 不支持挂起@QUERY 功能。
选择以下解决方案之一
1.可以打开root build.gradle

dependencies {
        //1.5.21 or 1.5.31
        classpath 'org.jetbrains.kotlin:kotlin-gradle-plugin:1.5.21'
    }

2.您可以将 $room-version 从 2.4.0-alpha03 更改为 2.4.0-beta01

def roomVersion = "2.4.0-alpha03"

3.可以使用LiveData或Flow作为函数返回类型

【讨论】：