diff --git a/src/mnesia_rocksdb.erl b/src/mnesia_rocksdb.erl
index 02bb474..df58cea 100644
--- a/src/mnesia_rocksdb.erl
+++ b/src/mnesia_rocksdb.erl
@@ -64,13 +64,13 @@
 
 %% schema level callbacks
 -export([semantics/2,
-	 check_definition/4,
-	 create_table/3,
-	 load_table/4,
-	 close_table/2,
-	 sync_close_table/2,
-	 delete_table/2,
-	 info/3]).
+         check_definition/4,
+         create_table/3,
+         load_table/4,
+         close_table/2,
+         sync_close_table/2,
+         delete_table/2,
+         info/3]).
 
 %% table synch calls
 -export([sender_init/4,
@@ -214,7 +214,6 @@ register(Alias) ->
 default_alias() ->
     rocksdb_copies.
 
-
 %% ----------------------------------------------------------------------------
 %% DEBUG API
 %% ----------------------------------------------------------------------------
@@ -519,13 +518,13 @@ info(_Alias, Tab, memory) ->
     end;
 info(Alias, Tab, size) ->
     case retrieve_size(Alias, Tab) of
-	{ok, Size} ->
-	    if Size < 10000 -> ok;
-	       true -> size_warning(Alias, Tab)
-	    end,
-	    Size;
-	Error ->
-	    Error
+        {ok, Size} ->
+            if Size < 10000 -> ok;
+               true -> size_warning(Alias, Tab)
+            end,
+            Size;
+        Error ->
+            Error
     end;
 info(_Alias, Tab, Item) ->
     case try_read_info(Tab, Item, undefined) of
@@ -537,10 +536,10 @@ info(_Alias, Tab, Item) ->
 
 retrieve_size(_Alias, Tab) ->
     case try_read_info(Tab, size, 0) of
-	{ok, Size} ->
-	    {ok, Size};
-	Error ->
-	    Error
+        {ok, Size} ->
+            {ok, Size};
+        Error ->
+            Error
     end.
 
 try_read_info(Tab, Item, Default) ->
@@ -637,10 +636,10 @@ first(Alias, Tab) ->
 %% PRIVATE ITERATOR
 i_first(I) ->
     case ?rocksdb:iterator_move(I, <<?DATA_START>>) of
-	{ok, First, _} ->
-	    decode_key(First);
-	_ ->
-	    '$end_of_table'
+        {ok, First, _} ->
+            decode_key(First);
+        _ ->
+            '$end_of_table'
     end.
 
 %% Not relevant for an ordered_set
@@ -662,12 +661,12 @@ last(Alias, Tab) ->
 %% PRIVATE ITERATOR
 i_last(I) ->
     case ?rocksdb:iterator_move(I, last) of
-	{ok, << ?INFO_TAG, _/binary >>, _} ->
-	    '$end_of_table';
-	{ok, Last, _} ->
-	    decode_key(Last);
-	_ ->
-	    '$end_of_table'
+        {ok, << ?INFO_TAG, _/binary >>, _} ->
+            '$end_of_table';
+        {ok, Last, _} ->
+            decode_key(Last);
+        _ ->
+            '$end_of_table'
     end.
 
 %% Since we replace the key with [] in the record, we have to put it back
@@ -676,33 +675,34 @@ lookup(Alias, Tab, Key) ->
     Enc = encode_key(Key),
     {Ref, Type} = call(Alias, Tab, get_ref),
     case Type of
-	bag -> lookup_bag(Ref, Key, Enc, keypos(Tab));
-	_ ->
-	    case ?rocksdb:get(Ref, Enc, []) of
-		{ok, EncVal} ->
-		    [setelement(keypos(Tab), decode_val(EncVal), Key)];
-		_ ->
-		    []
-	    end
+        bag ->
+            lookup_bag(Ref, Key, Enc, keypos(Tab));
+        _ ->
+            case ?rocksdb:get(Ref, Enc, []) of
+                {ok, EncVal} ->
+                    [setelement(keypos(Tab), decode_val(EncVal), Key)];
+                _ ->
+                    []
+            end
     end.
 
 lookup_bag(Ref, K, Enc, KP) ->
     Sz = byte_size(Enc),
     with_iterator(
       Ref, fun(I) ->
-		   lookup_bag_(Sz, Enc, ?rocksdb:iterator_move(I, Enc),
-			       K, I, KP)
-	   end).
+                   lookup_bag_(Sz, Enc, ?rocksdb:iterator_move(I, Enc),
+                               K, I, KP)
+           end).
 
 lookup_bag_(Sz, Enc, {ok, Enc, _}, K, I, KP) ->
     lookup_bag_(Sz, Enc, ?rocksdb:iterator_move(I, next), K, I, KP);
 lookup_bag_(Sz, Enc, Res, K, I, KP) ->
     case Res of
-	{ok, <<Enc:Sz/binary, _:?BAG_CNT>>, V} ->
-	    [setelement(KP, decode_val(V), K)|
-	     lookup_bag_(Sz, Enc, ?rocksdb:iterator_move(I, next), K, I, KP)];
-	_ ->
-	    []
+        {ok, <<Enc:Sz/binary, _:?BAG_CNT>>, V} ->
+            [setelement(KP, decode_val(V), K)|
+             lookup_bag_(Sz, Enc, ?rocksdb:iterator_move(I, next), K, I, KP)];
+        _ ->
+            []
     end.
 
 match_delete(Alias, Tab, Pat) when is_atom(Pat) ->
@@ -759,23 +759,23 @@ prev(Alias, Tab, Key0) ->
 %% PRIVATE ITERATOR
 i_prev(I, Key) ->
     case ?rocksdb:iterator_move(I, Key) of
-	{ok, _, _} ->
-	    i_move_to_prev(I, Key);
-	{error, invalid_iterator} ->
-	    i_last(I)
+        {ok, _, _} ->
+            i_move_to_prev(I, Key);
+        {error, invalid_iterator} ->
+            i_last(I)
     end.
 
 %% PRIVATE ITERATOR
 i_move_to_prev(I, Key) ->
     case ?rocksdb:iterator_move(I, prev) of
-	{ok, << ?INFO_TAG, _/binary >>, _} ->
-	    '$end_of_table';
-	{ok, Prev, _} when Prev < Key ->
-	    decode_key(Prev);
-	{ok, _, _} ->
-	    i_move_to_prev(I, Key);
-	_ ->
-	    '$end_of_table'
+        {ok, << ?INFO_TAG, _/binary >>, _} ->
+            '$end_of_table';
+        {ok, Prev, _} when Prev < Key ->
+            decode_key(Prev);
+        {ok, _, _} ->
+            i_move_to_prev(I, Key);
+        _ ->
+            '$end_of_table'
     end.
 
 repair_continuation(Cont, _Ms) ->
@@ -831,22 +831,22 @@ update_counter(Alias, Tab, C, Val) when is_integer(Val) ->
 do_update_counter(C, Val, Ref, St) ->
     Enc = encode_key(C),
     case ?rocksdb:get(Ref, Enc, [{fill_cache, true}]) of
-	{ok, EncVal} ->
-	    case decode_val(EncVal) of
-		{_, _, Old} = Rec when is_integer(Old) ->
-		    Res = Old+Val,
-		    return_catch(
+        {ok, EncVal} ->
+            case decode_val(EncVal) of
+                {_, _, Old} = Rec when is_integer(Old) ->
+                    Res = Old+Val,
+                    return_catch(
                       fun() ->
                               db_put(Ref, Enc,
                                      encode_val(
                                        setelement(3, Rec, Res)),
                                      [], St)
                       end);
-		_ ->
-		    badarg
-	    end;
-	_ ->
-	    badarg
+                _ ->
+                    badarg
+            end;
+        _ ->
+            badarg
     end.
 
 %% PRIVATE
@@ -1208,15 +1208,14 @@ do_insert(K, V, #st{ets = Ets, ref = Ref, type = bag, maintain_size = true} = St
 do_insert(K, V, #st{ref = Ref, maintain_size = false} = St) ->
     return_catch(fun() -> db_put(Ref, K, V, [], St) end);
 do_insert(K, V, #st{ets = Ets, ref = Ref, maintain_size = true} = St) ->
-    IsNew =
-	case ?rocksdb:get(Ref, K, []) of
-	    {ok, _} ->
-		false;
-	    _ ->
-		true
-	end,
+    IsNew = case ?rocksdb:get(Ref, K, []) of
+                {ok, _} ->
+                    false;
+                _ ->
+                    true
+            end,
     case IsNew of
-	true ->
+        true ->
             return_catch(
               fun() ->
                       NewSz = read_info(size, 0, Ets) + 1,
@@ -1226,8 +1225,8 @@ do_insert(K, V, #st{ets = Ets, ref = Ref, maintain_size = true} = St) ->
                                    write, [Ref, L, []], St), % may throw
                       ets_insert_info(Ets, size, NewSz)
               end);
-	false ->
-	    return_catch(fun() -> db_put(Ref, K, V, [], St) end)
+        false ->
+            return_catch(fun() -> db_put(Ref, K, V, [], St) end)
     end,
     ok.
 
@@ -1235,9 +1234,9 @@ do_insert_bag(Ref, K, V, CurSz, St) ->
     KSz = byte_size(K),
     with_iterator(
       Ref, fun(I) ->
-		   do_insert_bag_(
-		     KSz, K, ?rocksdb:iterator_move(I, K), I, V, 0, Ref, CurSz, St)
-	   end).
+                   do_insert_bag_(
+                     KSz, K, ?rocksdb:iterator_move(I, K), I, V, 0, Ref, CurSz, St)
+           end).
 
 
 %% There's a potential access pattern that would force counters to
@@ -1245,21 +1244,21 @@ do_insert_bag(Ref, K, V, CurSz, St) ->
 %% with compaction. TODO.
 do_insert_bag_(Sz, K, Res, I, V, Prev, Ref, TSz, St) when Prev < ?MAX_BAG ->
     case Res of
-	{ok, <<K:Sz/binary, _:?BAG_CNT>>, V} ->
-	    %% object exists
-	    TSz;
-	{ok, <<K:Sz/binary, N:?BAG_CNT>>, _} ->
-	    do_insert_bag_(
-	      Sz, K, ?rocksdb:iterator_move(I, next), I, V, N, Ref, TSz, St);
-	_ when TSz =:= false ->
-	    Key = <<K/binary, (Prev+1):?BAG_CNT>>,
-	    db_put(Ref, Key, V, [], St);
-	_ ->
-	    NewSz = TSz + 1,
-	    {Ki, Vi} = info_obj(size, NewSz),
-	    Key = <<K/binary, (Prev+1):?BAG_CNT>>,
-	    db_write(Ref, [{put, Ki, Vi}, {put, Key, V}], [], St),
-	    NewSz
+        {ok, <<K:Sz/binary, _:?BAG_CNT>>, V} ->
+            %% object exists
+            TSz;
+        {ok, <<K:Sz/binary, N:?BAG_CNT>>, _} ->
+            do_insert_bag_(
+              Sz, K, ?rocksdb:iterator_move(I, next), I, V, N, Ref, TSz, St);
+        _ when TSz =:= false ->
+            Key = <<K/binary, (Prev+1):?BAG_CNT>>,
+            db_put(Ref, Key, V, [], St);
+        _ ->
+            NewSz = TSz + 1,
+            {Ki, Vi} = info_obj(size, NewSz),
+            Key = <<K/binary, (Prev+1):?BAG_CNT>>,
+            db_write(Ref, [{put, Ki, Vi}, {put, Key, V}], [], St),
+            NewSz
     end.
 
 %% server-side part
@@ -1279,7 +1278,7 @@ do_delete(Key, #st{ref = Ref, maintain_size = false} = St) ->
 do_delete(Key, #st{ets = Ets, ref = Ref, maintain_size = true} = St) ->
     CurSz = read_info(size, 0, Ets),
     case ?rocksdb:get(Ref, Key, [{fill_cache,true}]) of
-	{ok, _} ->
+        {ok, _} ->
             return_catch(
               fun() ->
                       NewSz = CurSz -1,
@@ -1287,85 +1286,84 @@ do_delete(Key, #st{ets = Ets, ref = Ref, maintain_size = true} = St) ->
                       ok = db_write(Ref, [{delete, Key}, {put, Ki, Vi}], [], St),
                       ets_insert_info(Ets, size, NewSz)
               end);
-	not_found ->
-	    false
+        not_found ->
+            false
     end.
 
 do_delete_bag(Sz, Key, Ref, TSz, St) ->
-    Found = 
-	with_iterator(
-	  Ref, fun(I) ->
-		       do_delete_bag_(Sz, Key, ?rocksdb:iterator_move(I, Key),
-				      Ref, I)
-	       end),
+    Found = with_iterator(
+              Ref, fun(I) ->
+                           do_delete_bag_(Sz, Key, ?rocksdb:iterator_move(I, Key),
+                                          Ref, I)
+                   end),
     case {Found, TSz} of
-	{[], _} ->
-	    TSz;
-	{_, false} ->
-	    db_write(Ref, [{delete, K} || K <- Found], [], St);
-	{_, _} ->
-	    N = length(Found),
-	    NewSz = TSz - N,
-	    {Ki, Vi} = info_obj(size, NewSz),
-	    db_write(Ref, [{put, Ki, Vi} |
+        {[], _} ->
+            TSz;
+        {_, false} ->
+            db_write(Ref, [{delete, K} || K <- Found], [], St);
+        {_, _} ->
+            N = length(Found),
+            NewSz = TSz - N,
+            {Ki, Vi} = info_obj(size, NewSz),
+            db_write(Ref, [{put, Ki, Vi} |
                            [{delete, K} || K <- Found]], [], St),
-	    NewSz
+            NewSz
     end.
 
 do_delete_bag_(Sz, K, Res, Ref, I) ->
     case Res of
-	{ok, K, _} ->
-	    do_delete_bag_(Sz, K, ?rocksdb:iterator_move(I, next),
-			   Ref, I);
-	{ok, <<K:Sz/binary, _:?BAG_CNT>> = Key, _} ->
-	    [Key |
-	     do_delete_bag_(Sz, K, ?rocksdb:iterator_move(I, next),
-			    Ref, I)];
-	_ ->
-	    []
+        {ok, K, _} ->
+            do_delete_bag_(Sz, K, ?rocksdb:iterator_move(I, next),
+                           Ref, I);
+        {ok, <<K:Sz/binary, _:?BAG_CNT>> = Key, _} ->
+            [Key |
+             do_delete_bag_(Sz, K, ?rocksdb:iterator_move(I, next),
+                            Ref, I)];
+        _ ->
+            []
     end.
 
 do_match_delete(Pat, #st{ets = Ets, ref = Ref, tab = Tab, type = Type,
-			 maintain_size = MaintainSize} = St) ->
+                         maintain_size = MaintainSize} = St) ->
     Fun = fun(_, Key, Acc) -> [Key|Acc] end,
     Keys = do_fold(Ref, Tab, Type, Fun, [], [{Pat,[],['$_']}], 30),
     case {Keys, MaintainSize} of
-	{[], _} ->
-	    ok;
-	{_, false} ->
-	    db_write(Ref, [{delete, K} || K <- Keys], [], St),
-	    ok;
-	{_, true} ->
-	    CurSz = read_info(size, 0, Ets),
-	    NewSz = max(CurSz - length(Keys), 0),
-	    {Ki, Vi} = info_obj(size, NewSz),
-	    db_write(Ref, [{put, Ki, Vi} |
+        {[], _} ->
+            ok;
+        {_, false} ->
+            db_write(Ref, [{delete, K} || K <- Keys], [], St),
+            ok;
+        {_, true} ->
+            CurSz = read_info(size, 0, Ets),
+            NewSz = max(CurSz - length(Keys), 0),
+            {Ki, Vi} = info_obj(size, NewSz),
+            db_write(Ref, [{put, Ki, Vi} |
                            [{delete, K} || K <- Keys]], [], St),
-	    ets_insert_info(Ets, size, NewSz),
-	    ok
+            ets_insert_info(Ets, size, NewSz),
+            ok
     end.
 
 recover_size_info(#st{ ref = Ref
-		     , tab = Tab
-		     , type = Type
-		     , maintain_size = MaintainSize
-		     } = St) ->
+                       , tab = Tab
+                       , type = Type
+                       , maintain_size = MaintainSize
+                     } = St) ->
     %% TODO: shall_update_size_info is obsolete, remove
     case shall_update_size_info(Tab) of
-	true ->
-	    Sz = do_fold(Ref, Tab, Type, fun(_, Acc) -> Acc+1 end,
-			 0, [{'_',[],['$_']}], 3),
-	    write_info_(size, Sz, St);
-	false ->
-	    case MaintainSize of
-		true ->
-		    %% info initialized by rocksdb_to_ets/2
-		    %% TODO: if there is no stored size, recompute it
-		    ignore;
-		false ->
-		    %% size is not maintained, ensure it's marked accordingly
-		    delete_info_(size, St)
-	    end
+        true ->
+            Sz = do_fold(Ref, Tab, Type, fun(_, Acc) -> Acc+1 end,
+                         0, [{'_',[],['$_']}], 3),
+            write_info_(size, Sz, St);
+        false ->
+            case MaintainSize of
+                true ->
+                    %% info initialized by rocksdb_to_ets/2
+                    %% TODO: if there is no stored size, recompute it
+                    ignore;
+                false ->
+                    %% size is not maintained, ensure it's marked accordingly
+                    delete_info_(size, St)
+            end
     end,
     St.
 
@@ -1453,15 +1451,14 @@ do_select(Ref, Tab, _Type, MS, AccKeys, Limit) when is_boolean(AccKeys) ->
 i_do_select(I, #sel{keypat = Pfx,
                     compiled_ms = MS,
                     limit = Limit} = Sel, AccKeys, Acc) ->
-    StartKey =
-        case Pfx of
-            <<>> ->
-                <<?DATA_START>>;
-            _ ->
-                Pfx
-	end,
+    StartKey = case Pfx of
+                   <<>> ->
+                       <<?DATA_START>>;
+                   _ ->
+                       Pfx
+               end,
     select_traverse(?rocksdb:iterator_move(I, StartKey), Limit,
-		    Pfx, MS, I, Sel, AccKeys, Acc).
+                    Pfx, MS, I, Sel, AccKeys, Acc).
 
 needs_key_only([{HP,_,Body}]) ->
     BodyVars = lists:flatmap(fun extract_vars/1, Body),
@@ -1525,18 +1522,18 @@ map_vars([], _) ->
 select_traverse({ok, K, V}, Limit, Pfx, MS, I, #sel{tab = Tab} = Sel,
                 AccKeys, Acc) ->
     case is_prefix(Pfx, K) of
-	true ->
-	    Rec = setelement(keypos(Tab), decode_val(V), decode_key(K)),
-	    case ets:match_spec_run([Rec], MS) of
-		[] ->
-		    select_traverse(
-		      ?rocksdb:iterator_move(I, next), Limit, Pfx, MS,
-		      I, Sel, AccKeys, Acc);
-		[Match] ->
+        true ->
+            Rec = setelement(keypos(Tab), decode_val(V), decode_key(K)),
+            case ets:match_spec_run([Rec], MS) of
+                [] ->
+                    select_traverse(
+                      ?rocksdb:iterator_move(I, next), Limit, Pfx, MS,
+                      I, Sel, AccKeys, Acc);
+                [Match] ->
                     Acc1 = if AccKeys ->
-                                   [{K, Match}|Acc];
+                                  [{K, Match}|Acc];
                               true ->
-                                   [Match|Acc]
+                                  [Match|Acc]
                            end,
                     traverse_continue(K, decr(Limit), Pfx, MS, I, Sel, AccKeys, Acc1)
             end;
@@ -1563,22 +1560,22 @@ decr(infinity) ->
 traverse_continue(K, 0, Pfx, MS, _I, #sel{limit = Limit, ref = Ref} = Sel, AccKeys, Acc) ->
     {lists:reverse(Acc),
      fun() ->
-	     with_iterator(Ref,
-			   fun(NewI) ->
+             with_iterator(Ref,
+                           fun(NewI) ->
                                    select_traverse(iterator_next(NewI, K),
                                                    Limit, Pfx, MS, NewI, Sel,
                                                    AccKeys, [])
-			   end)
+                           end)
      end};
 traverse_continue(_K, Limit, Pfx, MS, I, Sel, AccKeys, Acc) ->
     select_traverse(?rocksdb:iterator_move(I, next), Limit, Pfx, MS, I, Sel, AccKeys, Acc).
 
 iterator_next(I, K) ->
     case ?rocksdb:iterator_move(I, K) of
-	{ok, K, _} ->
-	    ?rocksdb:iterator_move(I, next);
-	Other ->
-	    Other
+        {ok, K, _} ->
+            ?rocksdb:iterator_move(I, next);
+        Other ->
+            Other
     end.
 
 keypat([H|T], KeyPos) ->
@@ -1668,9 +1665,9 @@ valid_mnesia_op(Op) ->
      ; Op==warning
      ; Op==error
      ; Op==fatal ->
-            true;
+           true;
        true ->
-            false
+           false
     end.
 
 %% ----------------------------------------------------------------------------