diff --git a/core/rawdb/chain_freezer.go b/core/rawdb/chain_freezer.go
index 729e616daf..4fe85d843b 100644
--- a/core/rawdb/chain_freezer.go
+++ b/core/rawdb/chain_freezer.go
@@ -386,6 +386,8 @@ func (f *chainFreezer) Ancient(kind string, number uint64) ([]byte, error) {
 		return f.eradb.GetRawBody(number)
 	case ChainFreezerReceiptTable:
 		return f.eradb.GetRawReceipts(number)
+	case ChainFreezerBALTable:
+		return nil, errOutOfBounds
 	}
 	return nil, errUnknownTable
 }
diff --git a/core/rawdb/freezer.go b/core/rawdb/freezer.go
index 5fa57bf6e1..d3dbffedd2 100644
--- a/core/rawdb/freezer.go
+++ b/core/rawdb/freezer.go
@@ -77,8 +77,8 @@ type Freezer struct {
 // data according to the given parameters.
 //
 // The 'tables' argument defines the freezer tables and their configuration.
-// Each value is a freezerTableConfig specifying whether snappy compression is
-// disabled (noSnappy) and whether the table is prunable (prunable).
+// Each value is a freezerTableConfig describing whether Snappy compression
+// is disabled (noSnappy) and which tail group the table belongs to.
 func NewFreezer(datadir string, namespace string, readonly bool, maxTableSize uint32, tables map[string]freezerTableConfig) (*Freezer, error) {
 	// Create the initial freezer object
 	var (