aboutsummaryrefslogtreecommitdiff
path: root/src/p1_mnesia.erl
diff options
context:
space:
mode:
Diffstat (limited to 'src/p1_mnesia.erl')
-rw-r--r--src/p1_mnesia.erl29
1 files changed, 16 insertions, 13 deletions
diff --git a/src/p1_mnesia.erl b/src/p1_mnesia.erl
index 6d9018640..97acfc352 100644
--- a/src/p1_mnesia.erl
+++ b/src/p1_mnesia.erl
@@ -4,16 +4,19 @@
%% Erlang Public License along with this software. If not, it can be
%% retrieved via the world wide web 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.
%%
+%%
%% The Initial Developer of the Original Code is ProcessOne.
%% Portions created by ProcessOne are Copyright 2006-2013, ProcessOne
%% All Rights Reserved.''
-module(p1_mnesia).
+
-author('mickael.remond@process-one.net').
-export([count_records/2]).
@@ -23,21 +26,21 @@
%% The count has been written to use the fewest possible memory by
%% getting the record by small increment and by using continuation.
-define(BATCHSIZE, 100).
+
count_records(Tab, MatchExpression) ->
- %% the result contains list of [] for each match: We do not need
- %% actual values as we only count the data.
- case mnesia:select(Tab, [{MatchExpression, [], [[]]}], ?BATCHSIZE, read) of
- {Result,Cont} ->
- Count = length(Result),
- count_records_cont(Cont, Count);
- '$end_of_table' ->
- 0
+ case mnesia:select(Tab, [{MatchExpression, [], [[]]}],
+ ?BATCHSIZE, read)
+ of
+ {Result, Cont} ->
+ Count = length(Result),
+ count_records_cont(Cont, Count);
+ '$end_of_table' -> 0
end.
+
count_records_cont(Cont, Count) ->
case mnesia:select(Cont) of
- {Result,Cont} ->
- NewCount = Count + length(Result),
- count_records_cont(Cont, NewCount);
- '$end_of_table' ->
- Count
+ {Result, Cont} ->
+ NewCount = Count + length(Result),
+ count_records_cont(Cont, NewCount);
+ '$end_of_table' -> Count
end.