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Posted to commits@couchdb.apache.org by da...@apache.org on 2020/02/10 18:41:01 UTC
[couchdb] 03/16: Change map indexes to be stored in one row
This is an automated email from the ASF dual-hosted git repository.
davisp pushed a commit to branch prototype/fdb-layer-get-dbs-info
in repository https://gitbox.apache.org/repos/asf/couchdb.git
commit f1876277e447b0da8483e067fd077cc4b16f25eb
Author: Garren Smith <ga...@gmail.com>
AuthorDate: Thu Jan 16 15:29:08 2020 +0200
Change map indexes to be stored in one row
Changes map indexes to store the original key and value in a single
FDB row.
---
src/couch_views/include/couch_views.hrl | 3 -
src/couch_views/src/couch_views_fdb.erl | 126 ++++-------------------------
src/couch_views/src/couch_views_reader.erl | 2 +-
3 files changed, 17 insertions(+), 114 deletions(-)
diff --git a/src/couch_views/include/couch_views.hrl b/src/couch_views/include/couch_views.hrl
index 2e443eb..642431d 100644
--- a/src/couch_views/include/couch_views.hrl
+++ b/src/couch_views/include/couch_views.hrl
@@ -19,8 +19,5 @@
-define(VIEW_ROW_COUNT, 0).
-define(VIEW_KV_SIZE, 1).
--define(VIEW_ROW_KEY, 0).
--define(VIEW_ROW_VALUE, 1).
-
% jobs api
-define(INDEX_JOB_TYPE, <<"views">>).
diff --git a/src/couch_views/src/couch_views_fdb.erl b/src/couch_views/src/couch_views_fdb.erl
index 60ce300..98cff46 100644
--- a/src/couch_views/src/couch_views_fdb.erl
+++ b/src/couch_views/src/couch_views_fdb.erl
@@ -95,31 +95,14 @@ fold_map_idx(TxDb, Sig, ViewId, Options, Callback, Acc0) ->
MapIdxPrefix = map_idx_prefix(DbPrefix, Sig, ViewId),
FoldAcc = #{
prefix => MapIdxPrefix,
- sort_key => undefined,
- docid => undefined,
- dupe_id => undefined,
callback => Callback,
acc => Acc0
- },
-
- {Fun, Acc} = case fabric2_util:get_value(dir, Options, fwd) of
- fwd ->
- FwdAcc = FoldAcc#{
- next => key,
- key => undefined
- },
- {fun fold_fwd/2, FwdAcc};
- rev ->
- RevAcc = FoldAcc#{
- next => value,
- value => undefined
- },
- {fun fold_rev/2, RevAcc}
- end,
+ },
+ Fun = fun fold_fwd/2,
#{
acc := Acc1
- } = fabric2_fdb:fold_range(TxDb, MapIdxPrefix, Fun, Acc, Options),
+ } = fabric2_fdb:fold_range(TxDb, MapIdxPrefix, Fun, FoldAcc, Options),
Acc1.
@@ -169,110 +152,34 @@ write_doc(TxDb, Sig, ViewIds, Doc) ->
end, lists:zip(ViewIds, Results)).
-% For each row in a map view there are two rows stored in
-% FoundationDB:
+% For each row in a map view we store the the key/value
+% in FoundationDB:
%
-% `(EncodedSortKey, EncodedKey)`
-% `(EncodedSortKey, EncodedValue)`
+% `(EncodedSortKey, (EncodedKey, EncodedValue))`
%
% The difference between `EncodedSortKey` and `EndcodedKey` is
% the use of `couch_util:get_sort_key/1` which turns UTF-8
% strings into binaries that are byte comparable. Given a sort
% key binary we cannot recover the input so to return unmodified
% user data we are forced to store the original.
-%
-% These two fold functions exist so that we can be fairly
-% forceful on our assertions about which rows to see. Since
-% when we're folding forward we'll see the key first. When
-% `descending=true` and we're folding in reverse we'll see
-% the value first.
-fold_fwd({RowKey, EncodedOriginalKey}, #{next := key} = Acc) ->
- #{
- prefix := Prefix
- } = Acc,
-
- {{SortKey, DocId}, DupeId, ?VIEW_ROW_KEY} =
- erlfdb_tuple:unpack(RowKey, Prefix),
- Acc#{
- next := value,
- key := couch_views_encoding:decode(EncodedOriginalKey),
- sort_key := SortKey,
- docid := DocId,
- dupe_id := DupeId
- };
-
-fold_fwd({RowKey, EncodedValue}, #{next := value} = Acc) ->
+fold_fwd({RowKey, PackedKeyValue}, Acc) ->
#{
prefix := Prefix,
- key := Key,
- sort_key := SortKey,
- docid := DocId,
- dupe_id := DupeId,
callback := UserCallback,
acc := UserAcc0
} = Acc,
- % We're asserting there that this row is paired
- % correctly with the previous row by relying on
- % a badmatch if any of these values don't match.
- {{SortKey, DocId}, DupeId, ?VIEW_ROW_VALUE} =
+ {{_SortKey, DocId}, _DupeId} =
erlfdb_tuple:unpack(RowKey, Prefix),
+ {EncodedOriginalKey, EncodedValue} = erlfdb_tuple:unpack(PackedKeyValue),
Value = couch_views_encoding:decode(EncodedValue),
- UserAcc1 = UserCallback(DocId, Key, Value, UserAcc0),
-
- Acc#{
- next := key,
- key := undefined,
- sort_key := undefined,
- docid := undefined,
- dupe_id := undefined,
- acc := UserAcc1
- }.
-
-
-fold_rev({RowKey, EncodedValue}, #{next := value} = Acc) ->
- #{
- prefix := Prefix
- } = Acc,
-
- {{SortKey, DocId}, DupeId, ?VIEW_ROW_VALUE} =
- erlfdb_tuple:unpack(RowKey, Prefix),
- Acc#{
- next := key,
- value := couch_views_encoding:decode(EncodedValue),
- sort_key := SortKey,
- docid := DocId,
- dupe_id := DupeId
- };
-
-fold_rev({RowKey, EncodedOriginalKey}, #{next := key} = Acc) ->
- #{
- prefix := Prefix,
- value := Value,
- sort_key := SortKey,
- docid := DocId,
- dupe_id := DupeId,
- callback := UserCallback,
- acc := UserAcc0
- } = Acc,
-
- % We're asserting there that this row is paired
- % correctly with the previous row by relying on
- % a badmatch if any of these values don't match.
- {{SortKey, DocId}, DupeId, ?VIEW_ROW_KEY} =
- erlfdb_tuple:unpack(RowKey, Prefix),
-
Key = couch_views_encoding:decode(EncodedOriginalKey),
+
UserAcc1 = UserCallback(DocId, Key, Value, UserAcc0),
Acc#{
- next := value,
- value := undefined,
- sort_key := undefined,
- docid := undefined,
- dupe_id := undefined,
acc := UserAcc1
}.
@@ -330,11 +237,10 @@ update_map_idx(TxDb, Sig, ViewId, DocId, ExistingKeys, NewRows) ->
KVsToAdd = process_rows(NewRows),
MapIdxPrefix = map_idx_prefix(DbPrefix, Sig, ViewId),
- lists:foreach(fun({DupeId, Key1, Key2, Val}) ->
- KK = map_idx_key(MapIdxPrefix, {Key1, DocId}, DupeId, ?VIEW_ROW_KEY),
- VK = map_idx_key(MapIdxPrefix, {Key1, DocId}, DupeId, ?VIEW_ROW_VALUE),
- ok = erlfdb:set(Tx, KK, Key2),
- ok = erlfdb:set(Tx, VK, Val)
+ lists:foreach(fun({DupeId, Key1, Key2, EV}) ->
+ KK = map_idx_key(MapIdxPrefix, {Key1, DocId}, DupeId),
+ Val = erlfdb_tuple:pack({Key2, EV}),
+ ok = erlfdb:set(Tx, KK, Val)
end, KVsToAdd).
@@ -400,8 +306,8 @@ map_idx_prefix(DbPrefix, Sig, ViewId) ->
erlfdb_tuple:pack(Key, DbPrefix).
-map_idx_key(MapIdxPrefix, MapKey, DupeId, Type) ->
- Key = {MapKey, DupeId, Type},
+map_idx_key(MapIdxPrefix, MapKey, DupeId) ->
+ Key = {MapKey, DupeId},
erlfdb_tuple:pack(Key, MapIdxPrefix).
diff --git a/src/couch_views/src/couch_views_reader.erl b/src/couch_views/src/couch_views_reader.erl
index 27671fb..76dbed1 100644
--- a/src/couch_views/src/couch_views_reader.erl
+++ b/src/couch_views/src/couch_views_reader.erl
@@ -183,7 +183,7 @@ mrargs_to_fdb_options(Args) ->
[
{dir, Direction},
- {limit, Limit * 2 + Skip * 2},
+ {limit, Limit + Skip},
{streaming_mode, want_all}
] ++ StartKeyOpts ++ EndKeyOpts.