Fix initial accumulator value for builtin_sum_rows
This a fixup for https://github.com/apache/couchdb-couch/pull/229.
The initial value for accumulator suppose to be 0. Since the result of
sum and count is integer. The problem was discovered by dialyzer.
COUCHDB-3305
diff --git a/src/couch_query_servers.erl b/src/couch_query_servers.erl
index ddc079e..63b0e39 100644
--- a/src/couch_query_servers.erl
+++ b/src/couch_query_servers.erl
@@ -142,13 +142,13 @@
builtin_reduce(_Re, [], _KVs, Acc) ->
{ok, lists:reverse(Acc)};
builtin_reduce(Re, [<<"_sum",_/binary>>|BuiltinReds], KVs, Acc) ->
- Sum = builtin_sum_rows(KVs, []),
+ Sum = builtin_sum_rows(KVs, 0),
builtin_reduce(Re, BuiltinReds, KVs, [Sum|Acc]);
builtin_reduce(reduce, [<<"_count",_/binary>>|BuiltinReds], KVs, Acc) ->
Count = length(KVs),
builtin_reduce(reduce, BuiltinReds, KVs, [Count|Acc]);
builtin_reduce(rereduce, [<<"_count",_/binary>>|BuiltinReds], KVs, Acc) ->
- Count = builtin_sum_rows(KVs, []),
+ Count = builtin_sum_rows(KVs, 0),
builtin_reduce(rereduce, BuiltinReds, KVs, [Count|Acc]);
builtin_reduce(Re, [<<"_stats",_/binary>>|BuiltinReds], KVs, Acc) ->
Stats = builtin_stats(Re, KVs),
