diff --git a/database/sortedset.go b/database/sortedset.go
index 41fb70e..842e845 100644
--- a/database/sortedset.go
+++ b/database/sortedset.go
@@ -600,9 +600,7 @@ func init() {
 	RegisterCommand("ZCard", execZCard, readFirstKey, nil, 2)
 	RegisterCommand("ZRange", execZRange, readFirstKey, nil, -4)
 	RegisterCommand("ZRangeByScore", execZRangeByScore, readFirstKey, nil, -4)
-	RegisterCommand("ZRange", execZRange, readFirstKey, nil, -4)
 	RegisterCommand("ZRevRange", execZRevRange, readFirstKey, nil, -4)
-	RegisterCommand("ZRangeByScore", execZRangeByScore, readFirstKey, nil, -4)
 	RegisterCommand("ZRevRangeByScore", execZRevRangeByScore, readFirstKey, nil, -4)
 	RegisterCommand("ZRem", execZRem, writeFirstKey, undoZRem, -3)
 	RegisterCommand("ZRemRangeByScore", execZRemRangeByScore, writeFirstKey, rollbackFirstKey, 4)