How to enforce datatype for Spark DataFrame read from json -


when read json (without schema) dataframe, numeric types going long. there way enforce integer type without giving specified json schema?

you can convert dataframe dataset case class

val df = seq((1,"ab"),(3,"ba")).todf("a","b")  case class test(a: int, b: string) df.as[test]

or duplicate column , recast df. 

import org.apache.spark.sql.types.{stringtype} df.withcolumn("newa", 'a.cast(stringtype))

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