diff --git a/example/csv/src/main/java/org/apache/calcite/adapter/csv/CsvTableScan.java b/example/csv/src/main/java/org/apache/calcite/adapter/csv/CsvTableScan.java
index a667a4499d07..b47d002be284 100644
--- a/example/csv/src/main/java/org/apache/calcite/adapter/csv/CsvTableScan.java
+++ b/example/csv/src/main/java/org/apache/calcite/adapter/csv/CsvTableScan.java
@@ -25,12 +25,14 @@
 import org.apache.calcite.linq4j.tree.Expressions;
 import org.apache.calcite.linq4j.tree.Primitive;
 import org.apache.calcite.plan.RelOptCluster;
+import org.apache.calcite.plan.RelOptCost;
 import org.apache.calcite.plan.RelOptPlanner;
 import org.apache.calcite.plan.RelOptTable;
 import org.apache.calcite.plan.RelTraitSet;
 import org.apache.calcite.rel.RelNode;
 import org.apache.calcite.rel.RelWriter;
 import org.apache.calcite.rel.core.TableScan;
+import org.apache.calcite.rel.metadata.RelMetadataQuery;
 import org.apache.calcite.rel.type.RelDataType;
 import org.apache.calcite.rel.type.RelDataTypeFactory;
 import org.apache.calcite.rel.type.RelDataTypeField;
@@ -79,6 +81,11 @@ protected CsvTableScan(RelOptCluster cluster, RelOptTable table,
     planner.addRule(CsvProjectTableScanRule.INSTANCE);
   }
 
+  @Override public RelOptCost computeSelfCost(RelOptPlanner planner, RelMetadataQuery mq) {
+    return super.computeSelfCost(planner, mq)
+        .multiplyBy(fields.length / table.getRowType().getFieldCount());
+  }
+
   public Result implement(EnumerableRelImplementor implementor, Prefer pref) {
     PhysType physType =
         PhysTypeImpl.of(
diff --git a/example/csv/src/test/java/org/apache/calcite/test/CsvTest.java b/example/csv/src/test/java/org/apache/calcite/test/CsvTest.java
index 785688b7c3b1..9fb63865cd52 100644
--- a/example/csv/src/test/java/org/apache/calcite/test/CsvTest.java
+++ b/example/csv/src/test/java/org/apache/calcite/test/CsvTest.java
@@ -241,6 +241,30 @@ public Void apply(ResultSet resultSet) {
         .ok();
   }
 
+  @Test public void testPushDownProjectAggregate() throws SQLException {
+    sql("smart", "explain plan for select gender, count(*) from EMPS group by gender")
+        .returns("PLAN=EnumerableAggregate(group=[{0}], EXPR$1=[COUNT()])\n"
+            + "  CsvTableScan(table=[[SALES, EMPS]], fields=[[3]])\n")
+        .ok();
+  }
+
+  @Test public void testPushDownProjectAggregateWithFilter() throws SQLException {
+    sql("smart", "explain plan for select max(empno) from EMPS where gender='F'")
+        .returns("PLAN=EnumerableAggregate(group=[{}], EXPR$0=[MAX($0)])\n"
+            + "  EnumerableCalc(expr#0..1=[{inputs}], expr#2=['F'], expr#3=[=($t1, $t2)], proj#0..1=[{exprs}], $condition=[$t3])\n"
+            + "    CsvTableScan(table=[[SALES, EMPS]], fields=[[0, 3]])\n")
+        .ok();
+  }
+
+  @Test public void testPushDownProjectAggregateNested() throws SQLException {
+    sql("smart", "explain plan for select gender, max(qty) from\n"
+        + "(select name, gender, count(*) qty from EMPS group by name, gender) t group by gender")
+        .returns("PLAN=EnumerableAggregate(group=[{1}], EXPR$1=[MAX($2)])\n"
+            + "  EnumerableAggregate(group=[{0, 1}], QTY=[COUNT()])\n"
+            + "    CsvTableScan(table=[[SALES, EMPS]], fields=[[1, 3]])\n")
+        .ok();
+  }
+
   @Test public void testFilterableSelect() throws SQLException {
     sql("filterable-model", "select name from EMPS").ok();
   }