Question

我正在尝试使用DataFrame API在两个时间戳之间返回行。

示例代码为：

val df = Seq(
    ("red", "2016-11-29 07:10:10.234"),
    ("green", "2016-11-29 07:10:10.234"),
    ("blue", "2016-11-29 07:10:10.234")).toDF("color", "date")

  df.where(unix_timestamp($"date", "yyyy-MM-dd HH:mm:ss.S").cast("timestamp").between(LocalDateTime.now(), LocalDateTime.now().minusHours(1))).show()

但它正在抛出Unsupported文字类型java.time.LocalDateTime错误。

Exception in thread "main" java.lang.RuntimeException: Unsupported literal type class java.time.LocalDateTime 2016-11-29T07:32:12.084
    at org.apache.spark.sql.catalyst.expressions.Literal$.apply(literals.scala:57)
    at org.apache.spark.sql.functions$.lit(functions.scala:101)
    at org.apache.spark.sql.Column.$greater$eq(Column.scala:438)
    at org.apache.spark.sql.Column.between(Column.scala:542)
    at com.sankar.SparkSQLTimestampDifference$.delayedEndpoint$com$sankar$SparkSQLTimestampDifference$1(SparkSQLTimestampDifference.scala:23)
    at com.sankar.SparkSQLTimestampDifference$delayedInit$body.apply(SparkSQLTimestampDifference.scala:7)
    at scala.Function0$class.apply$mcV$sp(Function0.scala:34)
    at scala.runtime.AbstractFunction0.apply$mcV$sp(AbstractFunction0.scala:12)
    at scala.App$$anonfun$main$1.apply(App.scala:76)
    at scala.App$$anonfun$main$1.apply(App.scala:76)
    at scala.collection.immutable.List.foreach(List.scala:381)
    at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:35)
    at scala.App$class.main(App.scala:76)
    at com.sankar.SparkSQLTimestampDifference$.main(SparkSQLTimestampDifference.scala:7)
    at com.sankar.SparkSQLTimestampDifference.main(SparkSQLTimestampDifference.scala)

Answer 1

当您在where子句中使用Timestamp时，您需要将LocalDateTime转换为Timestamp。另请注意，between的第一个参数是lowerBound，因此在您的情况下，LocalDateTime.now().minusHours(1)应该出现在LocalDateTime.now()之前。然后你就可以做到：

import java.time.LocalDateTime
import java.sql.Timestamp

df.where(
     unix_timestamp($"date", "yyyy-MM-dd HH:mm:ss.S")
       .cast("timestamp")
       .between(
          Timestamp.valueOf(LocalDateTime.now().minusHours(1)),
          Timestamp.valueOf(LocalDateTime.now())
       ))
  .show()

您将获得过滤后的DF

+-----+--------------------+
|color|                date|
+-----+--------------------+
|  red|2016-11-29 10:58:...|
+-----+--------------------+

Spark SQL在where子句的where子句之间？

1 个答案: