我在 Spark 中使用以下代码将我的 HBase/Phoenix 表的指定列加载到 Spark Dataframe 中。我可以指定要加载的列,但我可以指定哪些行吗?还是我必须加载所有行?
import org.apache.hadoop.conf.Configuration
import org.apache.spark.SparkContext
import org.apache.spark.sql.SQLContext
import org.apache.phoenix.spark._
sc.stop()
val sc = new SparkContext("local", "phoenix-test")
val df = sqlContext.phoenixTableAsDataFrame(
"TABLENAME", Array("ROWKEY", "CF.COL1","CF.COL2","CF.COL3"), conf = configuration
)
您可以在调用中添加谓词以限制检索哪些行,例如,
val df = sqlContext.phoenixTableAsDataFrame(
"TABLENAME", Array("ROWKEY", "CF.COL1","CF.COL2","CF.COL3"),
conf = configuration,
predicate = Some("ROWKEY IN ('1', '2')")
)