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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"]