Details
Description
After loading parquet files join is not working.
How to reproduce:
import org.apache.spark.sql._ import org.apache.spark.sql.types._ val arr1 = Array[Row](Row.apply(0, 0), Row.apply(1,1), Row.apply(2,2), Row.apply(3, 3), Row.apply(4, 4), Row.apply(5, 5), Row.apply(6, 6), Row.apply(7, 7)) val schema1 = StructType( StructField("id", IntegerType) :: StructField("value1", IntegerType) :: Nil) val df1 = sqlContext.createDataFrame(sc.parallelize(arr1), schema1) val arr2 = Array[Row](Row.apply(0, 0), Row.apply(1,1), Row.apply(2,2), Row.apply(3, 3), Row.apply(4, 4), Row.apply(5, 5), Row.apply(6, 6), Row.apply(7, 7)) val schema2 = StructType( StructField("otherId", IntegerType) :: StructField("value2", IntegerType) :: Nil) val df2 = sqlContext.createDataFrame(sc.parallelize(arr2), schema2) val res = df1.join(df2, df1("id")===df2("otherId")) df1.take(10) df2.take(10) res.count() res.take(10) df1.write.format("parquet").save("hdfs:///tmp/df1") df2.write.format("parquet").save("hdfs:///tmp/df2") val df1=sqlContext.read.parquet("hdfs:///tmp/df1/*.parquet") val df2=sqlContext.read.parquet("hdfs:///tmp/df2/*.parquet") val res = df1.join(df2, df1("id")===df2("otherId")) df1.take(10) df2.take(10) res.count() res.take(10)
Output
Array[org.apache.spark.sql.Row] = Array([0,0], [1,1], [2,2], [3,3], [4,4], [5,5], [6,6], [7,7])
Array[org.apache.spark.sql.Row] = Array([0,0], [1,1], [2,2], [3,3], [4,4], [5,5], [6,6], [7,7])
Long = 8
Array[org.apache.spark.sql.Row] = Array([0,0,0,0], [1,1,1,1], [2,2,2,2], [3,3,3,3], [4,4,4,4], [5,5,5,5], [6,6,6,6], [7,7,7,7])
After reading back:
Array[org.apache.spark.sql.Row] = Array([0,0], [1,1], [2,2], [3,3], [4,4], [5,5], [6,6], [7,7]) Array[org.apache.spark.sql.Row] = Array([0,0], [1,1], [2,2], [3,3], [4,4], [5,5], [6,6], [7,7]) Long = 4 Array[org.apache.spark.sql.Row] = Array([0,0,0,5], [2,2,2,null], [4,4,4,5], [6,6,6,null])