Apache Zeppelin不返回聚合數據

Question

我正在運行Apache Spark 2.0.1和Apache Zeppelin 0.6.2。

在飛艇，我有以下段落：

val df = sqlContext 
    .read 
    .format("org.apache.spark.sql.cassandra") 
    .options(Map("table" -> "iot_data2", "keyspace" -> "iot")) 
    .load() 

import org.apache.spark.sql.functions.{avg,round} 

val ts = $"updated_time".cast("long") 

val interval = (round(ts/3600L) * 3600.0).cast("timestamp").alias("time") 

df.groupBy($"a", $"b", $"date_bucket", interval).avg("t").createOrReplaceTempView("iot_avg") 

下一段我想要繪製的圖形，但對AVG（ 「T」）的值始終爲0：

%sql 
select time,avg("t") as avg_t from ble_temp_avg where a = '${a}' and b = '${b}' group by time order by time 

我想我錯過了一些非常明顯的東西，但我不知道它是一個新的Spark和Zeppelin用戶。

Answer 1

這似乎後，我重寫段落的工作：

在第一段：

val df = sqlContext 
    .read 
    .format("org.apache.spark.sql.cassandra") 
    .options(Map("table" -> "iot_data2", "keyspace" -> "iot")) 
    .load() 

import org.apache.spark.sql.functions.{avg,round} 

val ts = $"updated_time".cast("long") 

val interval = (round(ts/3600L) * 3600.0).cast("timestamp").alias("time") 

df.select($"a", $"b", $"date_bucket", interval, $"t").createOrReplaceTempView("iot_avg") 

在第二段：

%sql 
select time,avg(t) as avg_t from iot_avg where a = 'test1' and b = 'test2' group by time order by time