Updating a Single Column In Room Database-CodePudding

That's the function I'm using for updat

private fun updateSettingsDatabase(settingsDao: SettingsDao) {
        lifecycleScope.launch {
            settingsDao.update(SettingsEntity(
                1,
                nightMode=nightModeResult,
            ))
        }
}

@Query("SELECT * FROM `settings-table`")
fun fetchCurrentSettings(): Flow<List<SettingsEntity>>

I specified nightMode= because I thought that this way I'm only updating this colummn, but it turns out that it resets every column, how do I update a single column, while keeping the values the rest of the columns?

CodePudding user response：

Instead of creating new SettingsEntity object. Try to get the exact object first then update the value into it and finally update to Dao.

For Eg.,

@Query("SELECT * FROM `settings-table` where id=:id")
fun getSettingEntityById(id: Int): Flow<SettingsEntity>

@Insert(onConflict = OnConflictStrategy.REPLACE)
fun update(entity: SettingsEntity)


private fun updateSettingsDatabase(settingsDao: SettingsDao) {
    val entity = settingsDao.getSettingEntityById(1) // Replace 1 with exact id
    entity.updateValue(newValue)

    lifecycleScope.launch {
        settingsDao.update(entity)
    }
}

Hope this helps :)

CodePudding user response：

If it is single or few columns that you want to update then you can write custom query.

In your dao class

@Query("UPDATE settings-table SET nightMode = :nightModeResult WHERE id = :id")
fun updateNightMode(id: Int, nightModeResult: Any): Int