diff --git a/pkg/schema/field/timestamp.go b/pkg/schema/field/timestamp.go
index a96899542709d4cbab72978dce6dbf7e566d86b7..cc13bbea2dc0b657e20157a0bed3c9640b64ce0b 100644
--- a/pkg/schema/field/timestamp.go
+++ b/pkg/schema/field/timestamp.go
@@ -30,28 +30,10 @@ func (TimestampType) IsEmpty(v interface{}) bool {
 	return v == 0 || v == nil
 }
 
-func (TimestampType) Decode(_ context.Context, _ *Field, v interface{}) (interface{}, error) {
-	switch i := v.(type) {
-	case nil:
-		return nil, nil
-	case string:
-		duration, err := time.ParseDuration(i)
-		if err == nil {
-			return duration.Nanoseconds(), nil
-		}
-		t, err := time.Parse(time.TimeOnly, i)
-
-		if err == nil {
-			return t.AddDate(1, 0, 0).Sub(zeroTime).Nanoseconds(), nil
-		}
-		return nil, err
-	default:
-		return toTimestamp(i)
-	}
-}
-
 func toTimestamp(i interface{}) (interface{}, error) {
 	switch v := i.(type) {
+	case nil:
+		return nil, nil
 	case int64:
 		return v, nil
 	case int:
@@ -69,14 +51,30 @@ func toTimestamp(i interface{}) (interface{}, error) {
 	case uint32:
 		return int64(v), nil
 	default:
-		return 0, fmt.Errorf("unsupported value type: \"%T\"", v)
+		return 0, fmt.Errorf("unsupported value type: \"%T\"", i)
+	}
+}
+
+func (TimestampType) Decode(_ context.Context, _ *Field, v interface{}) (interface{}, error) {
+	switch i := v.(type) {
+	case string:
+		duration, err := time.ParseDuration(i)
+		if err == nil {
+			return duration.Nanoseconds(), nil
+		}
+		t, err := time.Parse(time.TimeOnly, i)
+
+		if err == nil {
+			return t.AddDate(1, 0, 0).Sub(zeroTime).Nanoseconds(), nil
+		}
+		return nil, err
+	default:
+		return toTimestamp(i)
 	}
 }
 
 func (TimestampType) Encode(_ context.Context, _ *Field, v interface{}) (interface{}, error) {
 	switch i := v.(type) {
-	case nil:
-		return nil, nil
 	default:
 		return toTimestamp(i)
 	}