android - how to query a specific string from a list of string in Android RoomDB

Question

Is it possible to query a specific string from a list of string in an Entity in RoomDB?

here is my Entity

 @Entity
data class Radical(
@PrimaryKey
val pkey: Int = 0,
@ColumnInfo(name="radical_name")
val radicalName: String,
@ColumnInfo(name="radical_strokes")
val radicalStrokes:List<String>
)

Then my interface would be like

@Query("SELECT * FROM RADICAL WHERE radicalStrokes == :radicalStrokes")
suspend fun fetchRadical(radicalStrokes: String): Radical

It returns null.

标签： androidkotlinandroid-room

Answer 1

您可以使用LIKE（与 contains() 方法相同）而不是 ==

例如

@Query("SELECT * FROM RADICAL WHERE radicalStrokes LIKE '%' ||  :radicalStrokes || '%' ")
suspend fun fetchRadical(radicalStrokes: String): Radical