Spark:编写一个带有空值的CSV作为空列

import org.apache.spark.sql.SparkSession
import org.apache.spark.sql.types.{StructType, StructField, StringType}

val spark = SparkSession.builder()
  .appName("CSV with Empty Column")
  .master("local")
  .getOrCreate()

val schema = StructType(Seq(
  StructField("col1", StringType, nullable = true),
  StructField("col2", StringType, nullable = true),
  StructField("col3", StringType, nullable = true),
  StructField("col4", StringType, nullable = true)
))

val df = spark.read
  .option("header", "true")
  .option("nullValue", "")
  .schema(schema)
  .csv("path/to/csv/file.csv")

// 显示DataFrame的内容
df.show()

// 进行其他操作，如筛选、聚合等
val filteredDF = df.filter(df("col1").isNotNull)