我有一个简单的程序,其数据集的列resource_serialized
具有JSON字符串,如下所示:
import org.apache.spark.SparkConf
object TestApp {
def main(args: Array[String]): Unit = {
val sparkConf: SparkConf = new SparkConf().setAppName("Loading Data").setMaster("local[*]")
val spark = org.apache.spark.sql.SparkSession
.builder
.config(sparkConf)
.appName("Test")
.getOrCreate()
val json = "[{\"resource_serialized\":\"{\\\"createdOn\\\":\\\"2000-07-20 00:00:00.0\\\",\\\"genderCode\\\":\\\"0\\\"}\",\"id\":\"00529e54-0f3d-4c76-9d3\"}]"
import spark.implicits._
val df = spark.read.json(Seq(json).toDS)
df.printSchema()
df.show()
}
}
打印的模式是:
root
|-- id: string (nullable = true)
|-- resource_serialized: string (nullable = true)
控制台上打印的数据集是:
+--------------------+--------------------+
| id| resource_serialized|
+--------------------+--------------------+
|00529e54-0f3d-4c7...|{"createdOn":"200...|
+--------------------+--------------------+
resource_serialized
字段具有json字符串,它是(来自调试控制台)
现在,我需要从该json字符串中创建数据集/数据框,我该如何实现呢?
使用from_json