Dr Mich Talebzadeh
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I just want to confirm my understanding of the physical plan generated by Spark SQL while reading from a Parquet file.HiWhen multiple predicates are pushed to the PrunedFilterScan, does Spark ensure that the Parquet file is not read multiple times while evaluating each predicate ?In general, is this optimization done for all columnar databases or file formats ?When I ran the following query in the spark-shell
> val nameDF = sqlContext.sql("SELECT name FROM parquetFile WHERE age = 50 AND name = 'someone'")I saw that both the filters are pushed, but I can't seem to find where it applies them to the file data.> nameDF.explain()
Project [name#112]+- Filter ((age#111L = 50) && (name#112 = someone))
+- Scan ParquetRelation[name#112,age#111L] InputPaths: file:/home/spark/spark-1.6.1/people.parquet,
PushedFilters: [EqualTo(age,50), EqualTo(name,someone)]