diff --git a/executor.go b/executor.go
index 82d2135ab..7d71088ba 100644
--- a/executor.go
+++ b/executor.go
@@ -16,6 +16,7 @@ package pilosa
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"sort"
 	"time"
@@ -909,6 +910,25 @@ type FieldRow struct {
 	RowKey string `json:"rowKey,omitempty"`
 }
 
+func (fr FieldRow) MarshalJSON() ([]byte, error) {
+	if fr.RowKey != "" {
+		return json.Marshal(struct {
+			Field  string `json:"field"`
+			RowKey string `json:"rowKey"`
+		}{
+			Field:  fr.Field,
+			RowKey: fr.RowKey,
+		})
+	}
+	return json.Marshal(struct {
+		Field string `json:"field"`
+		RowID uint64 `json:"rowID"`
+	}{
+		Field: fr.Field,
+		RowID: fr.RowID,
+	})
+}
+
 func (fr FieldRow) String() string {
 	return fmt.Sprintf("%s.%d", fr.Field, fr.RowID)
 }
diff --git a/executor_internal_test.go b/executor_internal_test.go
index 93ba86743..629d704db 100644
--- a/executor_internal_test.go
+++ b/executor_internal_test.go
@@ -1,6 +1,7 @@
 package pilosa
 
 import (
+	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"strings"
@@ -193,3 +194,31 @@ func TestFilterWithRows(t *testing.T) {
 	}
 
 }
+
+func TestFieldRowMarshalJSON(t *testing.T) {
+	fr := FieldRow{
+		Field:  "blah",
+		RowID:  0,
+		RowKey: "ha",
+	}
+	b, err := json.Marshal(fr)
+	if err != nil {
+		t.Fatalf("marshalling fieldrow: %v", err)
+	}
+	if string(b) != `{"field":"blah","rowKey":"ha"}` {
+		t.Fatalf("unexpected json: %s", b)
+	}
+
+	fr = FieldRow{
+		Field:  "blah",
+		RowID:  2,
+		RowKey: "",
+	}
+	b, err = json.Marshal(fr)
+	if err != nil {
+		t.Fatalf("marshalling fieldrow: %v", err)
+	}
+	if string(b) != `{"field":"blah","rowID":2}` {
+		t.Fatalf("unexpected json: %s", b)
+	}
+}
diff --git a/internal/public.proto b/internal/public.proto
index a102f1088..229fcfadd 100644
--- a/internal/public.proto
+++ b/internal/public.proto
@@ -11,7 +11,6 @@ message Row {
 message RowIdentifiers {
 	repeated uint64 Rows = 1;
 	repeated string Keys = 2;
-	//repeated Attr Attrs = 3;
 }
 
 message Pair {
@@ -81,7 +80,7 @@ message QueryResult {
 	uint64 N = 2;
 	repeated Pair Pairs = 3;
 	bool Changed = 4;
-  ValCount ValCount = 5;
+    ValCount ValCount = 5;
 	repeated uint64 RowIDs = 7;
 	repeated GroupCount GroupCounts = 8;
 	RowIdentifiers RowIdentifiers = 9;