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Revert "Fix read in order optimization for DESC sorting with FINAL"

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This reverts commit cf762347d5.
This commit is contained in:
vdimir 2023-02-09 10:47:45 +00:00
parent cf762347d5
commit a179528ea4
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GPG Key ID: 6EE4CE2BEDC51862
4 changed files with 6 additions and 42 deletions
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21
src/Processors/QueryPlan/ReadFromMergeTree.cpp
View File

@ -820,7 +820,6 @@ static void addMergingFinal(
Pipe ReadFromMergeTree::spreadMarkRangesAmongStreamsFinal(
RangesInDataParts && parts_with_ranges,
const Names & column_names,
const InputOrderInfoPtr & input_order_info,
ActionsDAGPtr & out_projection)
{
const auto & settings = context->getSettingsRef();
@ -895,19 +894,15 @@ Pipe ReadFromMergeTree::spreadMarkRangesAmongStreamsFinal(
if (new_parts.empty())
continue;
auto read_type = ReadFromMergeTree::ReadType::InOrder;
if (input_order_info && input_order_info->direction == -1)
read_type = ReadType::InReverseOrder;
if (num_streams > 1 && metadata_for_reading->hasPrimaryKey())
{
// Let's split parts into layers to ensure data parallelism of FINAL.
auto reading_step_getter = [this, &column_names, &info, read_type](auto parts)
auto reading_step_getter = [this, &column_names, &info](auto parts)
{
return this->read(
std::move(parts),
column_names,
read_type,
ReadFromMergeTree::ReadType::InOrder,
1 /* num_streams */,
0 /* min_marks_for_concurrent_read */,
info.use_uncompressed_cache);
@ -918,7 +913,7 @@ Pipe ReadFromMergeTree::spreadMarkRangesAmongStreamsFinal(
else
{
pipes.emplace_back(read(
std::move(new_parts), column_names, read_type, num_streams, 0, info.use_uncompressed_cache));
std::move(new_parts), column_names, ReadFromMergeTree::ReadType::InOrder, num_streams, 0, info.use_uncompressed_cache));
}
/// Drop temporary columns, added by 'sorting_key_expr'
@ -933,14 +928,11 @@ Pipe ReadFromMergeTree::spreadMarkRangesAmongStreamsFinal(
pipe.addSimpleTransform([sorting_expr](const Block & header)
{ return std::make_shared<ExpressionTransform>(header, sorting_expr); });
/// If do_not_merge_across_partitions_select_final is true
/// and there is only one part in partition with level > 0
/// then we won't postprocess this part
bool should_read_in_order = !input_order_info || input_order_info->direction == 0;
/// If do_not_merge_across_partitions_select_final is true and there is only one part in partition
/// with level > 0 then we won't postprocess this part
if (settings.do_not_merge_across_partitions_select_final &&
std::distance(parts_to_merge_ranges[range_index], parts_to_merge_ranges[range_index + 1]) == 1 &&
parts_to_merge_ranges[range_index]->data_part->info.level > 0 &&
!should_read_in_order)
parts_to_merge_ranges[range_index]->data_part->info.level > 0)
{
partition_pipes.emplace_back(Pipe::unitePipes(std::move(pipes)));
continue;
@ -1405,7 +1397,6 @@ void ReadFromMergeTree::initializePipeline(QueryPipelineBuilder & pipeline, cons
pipe = spreadMarkRangesAmongStreamsFinal(
std::move(result.parts_with_ranges),
column_names_to_read,
input_order_info,
result_projection);
}
else if (input_order_info)

1
src/Processors/QueryPlan/ReadFromMergeTree.h
View File

@ -237,7 +237,6 @@ private:
Pipe spreadMarkRangesAmongStreamsFinal(
RangesInDataParts && parts,
const Names & column_names,
const InputOrderInfoPtr & input_order_info,
ActionsDAGPtr & out_projection);
MergeTreeDataSelectAnalysisResultPtr selectRangesToRead(MergeTreeData::DataPartsVector parts) const;

5
tests/queries/0_stateless/25336_read_in_order_final_desc.reference
View File

@ -1,5 +0,0 @@
1900000050000 1
1900000040000 0.05
1900000030000 0
1900000020000 -0.0002
1900000010000 -1

21
tests/queries/0_stateless/25336_read_in_order_final_desc.sql
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@ -1,21 +0,0 @@
SET optimize_read_in_order = 1;
DROP TABLE IF EXISTS mytable;
CREATE TABLE mytable
(
timestamp UInt64,
insert_timestamp UInt64,
key UInt64,
value Float64
) ENGINE = ReplacingMergeTree(insert_timestamp)
PRIMARY KEY (key, timestamp)
ORDER BY (key, timestamp);
INSERT INTO mytable (timestamp, insert_timestamp, key, value) VALUES (1900000010000, 1675159000000, 5, 555), (1900000010000, 1675159770000, 5, -1), (1900000020000, 1675159770000, 5, -0.0002), (1900000030000, 1675159770000, 5, 0), (1900000020000, 1675159700000, 5, 555), (1900000040000, 1675159770000, 5, 0.05), (1900000050000, 1675159770000, 5, 1);
SELECT timestamp, value
FROM mytable FINAL
WHERE key = 5
ORDER BY timestamp DESC;
DROP TABLE IF EXISTS mytable;