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-rw-r--r--lib/mnesia/src/mnesia_index.erl60
1 files changed, 29 insertions, 31 deletions
diff --git a/lib/mnesia/src/mnesia_index.erl b/lib/mnesia/src/mnesia_index.erl
index 87cb58dae1..0c882c0df6 100644
--- a/lib/mnesia/src/mnesia_index.erl
+++ b/lib/mnesia/src/mnesia_index.erl
@@ -3,16 +3,17 @@
%%
%% Copyright Ericsson AB 1996-2014. All Rights Reserved.
%%
-%% The contents of this file are subject to the Erlang Public License,
-%% Version 1.1, (the "License"); you may not use this file except in
-%% compliance with the License. You should have received a copy of the
-%% Erlang Public License along with this software. If not, it can be
-%% retrieved online at http://www.erlang.org/.
-%%
-%% Software distributed under the License is distributed on an "AS IS"
-%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
-%% the License for the specific language governing rights and limitations
-%% under the License.
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%% http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
%%
%% %CopyrightEnd%
%%
@@ -45,21 +46,11 @@
del_transient/3,
del_index_table/3]).
--import(mnesia_lib, [verbose/2]).
+-import(mnesia_lib, [val/1, verbose/2]).
-include("mnesia.hrl").
-record(index, {setorbag, pos_list}).
-val(Var) ->
- case ?catch_val(Var) of
- {'EXIT', _ReASoN_} ->
- case mnesia_lib:other_val(Var) of
- error -> mnesia_lib:pr_other(Var, _ReASoN_);
- Val -> Val
- end;
- _VaLuE_ -> _VaLuE_
- end.
-
%% read an object list throuh its index table
%% we assume that table Tab has index on attribute number Pos
@@ -79,17 +70,24 @@ add_index(Index, Tab, Key, Obj, Old) ->
add_index2([{Pos, Ixt} |Tail], bag, Tab, K, Obj, OldRecs) ->
db_put(Ixt, {element(Pos, Obj), K}),
add_index2(Tail, bag, Tab, K, Obj, OldRecs);
-add_index2([{Pos, Ixt} |Tail], Type, Tab, K, Obj, OldRecs) ->
+add_index2([{Pos, Ixt} |Tail], Type, Tab, K, Obj, OldRecs0) ->
%% Remove old tuples in index if Tab is updated
- case OldRecs of
- undefined ->
- Old = mnesia_lib:db_get(Tab, K),
- del_ixes(Ixt, Old, Pos, K);
- Old ->
- del_ixes(Ixt, Old, Pos, K)
- end,
- db_put(Ixt, {element(Pos, Obj), K}),
- add_index2(Tail, Type, Tab, K, Obj, OldRecs);
+ OldRecs1 = case OldRecs0 of
+ undefined -> mnesia_lib:db_get(Tab, K);
+ _ -> OldRecs0
+ end,
+ IdxVal = element(Pos, Obj),
+ case [Old || Old <- OldRecs1, element(Pos, Old) =/= IdxVal] of
+ [] when OldRecs1 =:= [] -> %% Write
+ db_put(Ixt, {element(Pos, Obj), K}),
+ add_index2(Tail, Type, Tab, K, Obj, OldRecs0);
+ [] -> %% when OldRecs1 =/= [] Update without modifying index field
+ add_index2(Tail, Type, Tab, K, Obj, OldRecs0);
+ OldRecs -> %% Update
+ db_put(Ixt, {element(Pos, Obj), K}),
+ del_ixes(Ixt, OldRecs, Pos, K),
+ add_index2(Tail, Type, Tab, K, Obj, OldRecs0)
+ end;
add_index2([], _, _Tab, _K, _Obj, _) -> ok.
delete_index(Index, Tab, K) ->