[SPARK-26865][SQL] DataSourceV2Strategy should push normalized filters

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSourceStrategy.scala

@@ -426,6 +426,22 @@ case class DataSourceStrategy(conf: SQLConf) extends Strategy with Logging with
 }
 
 object DataSourceStrategy {
+  /**
+   * The attribute name of predicate could be different than the one in schema in case of
+   * case insensitive, we should change them to match the one in schema, so we do not need to
+   * worry about case sensitivity anymore.
+   */
+  protected[sql] def normalizeFilters(
+      filters: Seq[Expression],
+      attributes: Seq[AttributeReference]): Seq[Expression] = {
+    filters.filterNot(SubqueryExpression.hasSubquery).map { e =>
+      e transform {
+        case a: AttributeReference =>
+          a.withName(attributes.find(_.semanticEquals(a)).get.name)
+      }
+    }
+  }
+
   /**
    * Tries to translate a Catalyst [[Expression]] into data source [[Filter]].
    *

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/FileSourceStrategy.scala

@@ -147,15 +147,7 @@ object FileSourceStrategy extends Strategy with Logging {
       //  - filters that need to be evaluated again after the scan
       val filterSet = ExpressionSet(filters)
 
-      // The attribute name of predicate could be different than the one in schema in case of
-      // case insensitive, we should change them to match the one in schema, so we do not need to
-      // worry about case sensitivity anymore.
-      val normalizedFilters = filters.filterNot(SubqueryExpression.hasSubquery).map { e =>
-        e transform {
-          case a: AttributeReference =>
-            a.withName(l.output.find(_.semanticEquals(a)).get.name)
-        }
-      }
+      val normalizedFilters = DataSourceStrategy.normalizeFilters(filters, l.output)
 
       val partitionColumns =
         l.resolve(

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/DataSourceV2Strategy.scala

@@ -20,7 +20,7 @@ package org.apache.spark.sql.execution.datasources.v2
 import scala.collection.mutable
 
 import org.apache.spark.sql.{sources, AnalysisException, SaveMode, Strategy}
-import org.apache.spark.sql.catalyst.expressions.{And, AttributeReference, AttributeSet, Expression}
+import org.apache.spark.sql.catalyst.expressions.{And, AttributeReference, AttributeSet, Expression, SubqueryExpression}
 import org.apache.spark.sql.catalyst.planning.PhysicalOperation
 import org.apache.spark.sql.catalyst.plans.logical.{AppendData, LogicalPlan, Repartition}
 import org.apache.spark.sql.execution.{FilterExec, ProjectExec, SparkPlan}
@@ -104,10 +104,13 @@ object DataSourceV2Strategy extends Strategy {
   override def apply(plan: LogicalPlan): Seq[SparkPlan] = plan match {
     case PhysicalOperation(project, filters, relation: DataSourceV2Relation) =>
       val scanBuilder = relation.newScanBuilder()
+
+      val normalizedFilters = DataSourceStrategy.normalizeFilters(filters, relation.output)
+
       // `pushedFilters` will be pushed down and evaluated in the underlying data sources.
       // `postScanFilters` need to be evaluated after the scan.
       // `postScanFilters` and `pushedFilters` can overlap, e.g. the parquet row group filter.
-      val (pushedFilters, postScanFilters) = pushFilters(scanBuilder, filters)
+      val (pushedFilters, postScanFilters) = pushFilters(scanBuilder, normalizedFilters)
       val (scan, output) = pruneColumns(scanBuilder, relation, project ++ postScanFilters)
       logInfo(
         s"""

sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/DataSourceStrategySuite.scala

@@ -219,6 +219,11 @@ class DataSourceStrategySuite extends PlanTest with SharedSQLContext {
         IsNotNull(attrInt))), None)
   }
 
+  test("SPARK-26865 DataSourceV2Strategy should push normalized filters") {
+    val attrInt = 'cint.int
+    DataSourceStrategy.normalizeFilters(Seq(IsNotNull(attrInt.withName("CiNt"))), Seq(attrInt))
+  }
+
   /**
    * Translate the given Catalyst [[Expression]] into data source [[sources.Filter]]
    * then verify against the given [[sources.Filter]].