类型投影
默认情况下,查询将返回一个带有你投影的数据类,但你可以使用类型安全的映射器来覆盖该行为。
kotlin
val selectAllNames = playerQueries.selectAll(
mapper = { player_number, full_name -> full_name.toUppercase() }
)
println(selectAllNames.executeAsList())
// Prints ["RYAN GETZLAF", "COREY PERRY"]
通常,你应该尽可能利用 SQL 来进行自定义投影。
sql
selectNames:
SELECT upper(full_name)
FROM hockeyPlayer;
kotlin
val selectAllNames = playerQueries.selectNames()
println(selectAllNames.executeAsList())
// Prints ["RYAN GETZLAF", "COREY PERRY"]