Spark不能查询它能看到的配置单元表？

Question

然后，如果我运行这个命令来获取设施表的计数：val facTable=hivec.hql（“select count(*)from facility”），我将得到以下输出，我认为它无法找到要查询它的设施表：

scala> val facTable = hiveC.hql("select count(*) from facility")
warning: there were 1 deprecation warning(s); re-run with -deprecation for details
14/12/26 10:27:26 WARN HiveConf: DEPRECATED: Configuration property hive.metastore.local no longer has any effect. Make sure to provide a valid value for hive.metastore.uris if you are connecting to a remote metastore.

14/12/26 10:27:26 INFO ParseDriver: Parsing command: select count(*) from facility
14/12/26 10:27:26 INFO ParseDriver: Parse Completed
14/12/26 10:27:26 INFO MemoryStore: ensureFreeSpace(355177) called with curMem=0, maxMem=277842493
14/12/26 10:27:26 INFO MemoryStore: Block broadcast_0 stored as values in memory (estimated size 346.9 KB, free 264.6 MB)
14/12/26 10:27:26 INFO MemoryStore: ensureFreeSpace(50689) called with curMem=355177, maxMem=277842493
14/12/26 10:27:26 INFO MemoryStore: Block broadcast_0_piece0 stored as bytes in memory (estimated size 49.5 KB, free 264.6 MB)
14/12/26 10:27:26 INFO BlockManagerInfo: Added broadcast_0_piece0 in memory on 10.0.2.15:45305 (size: 49.5 KB, free: 264.9 MB)
14/12/26 10:27:26 INFO BlockManagerMaster: Updated info of block broadcast_0_piece0
14/12/26 10:27:26 INFO SparkContext: Created broadcast 0 from broadcast at TableReader.scala:68

facTable: org.apache.spark.sql.SchemaRDD = 
SchemaRDD[2] at RDD at SchemaRDD.scala:108
== Query Plan ==
== Physical Plan ==

Aggregate false, [], [Coalesce(SUM(PartialCount#38L),0) AS _c0#5L]
 Exchange SinglePartition
  Aggregate true, [], [COUNT(1) AS PartialCount#38L]
   HiveTableScan [], (MetastoreRelation default, facility, None), None

如能提供任何协助，将不胜感激。谢了。

Answer 1

scala> val facTable = hiveC.hql("select count(*) from facility")

太棒了！你有一个RDD，现在你想用它做什么？

scala> facTable.collect()

请记住，RDD是数据之上的一个抽象，只有在调用对其执行的操作（如collect()或count()）时，RDD才会具体化。

如果您试图使用一个不存在的表名，您将得到一个非常明显的错误。