Merge pull request #10131 from ClickHouse/fix-extremes-for-processors

Fix extremes for processors
This commit is contained in:
alexey-milovidov 2020-04-12 02:31:39 +03:00 committed by GitHub
commit 0782052768
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14 changed files with 410 additions and 91 deletions

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@ -82,7 +82,16 @@ Pipe createLocalStream(const ASTPtr & query_ast, const Block & header, const Con
/// This flag means that pipeline must be tree-shaped,
/// so we can't enable processors for InterpreterSelectQuery here.
auto stream = interpreter.execute().in;
Pipe pipe(std::make_shared<SourceFromInputStream>(std::move(stream)));
auto source = std::make_shared<SourceFromInputStream>(std::move(stream));
bool add_totals_and_extremes_port = processed_stage == QueryProcessingStage::Complete;
if (add_totals_and_extremes_port)
{
source->addTotalsPort();
source->addExtremesPort();
}
Pipe pipe(std::move(source));
pipe.addSimpleTransform(std::make_shared<ConvertingTransform>(
pipe.getHeader(), header, ConvertingTransform::MatchColumnsMode::Name, context));
@ -130,7 +139,7 @@ void SelectStreamFactory::createForShard(
Pipes & res)
{
bool force_add_agg_info = processed_stage == QueryProcessingStage::WithMergeableState;
bool add_totals_port = processed_stage == QueryProcessingStage::Complete;
bool add_totals_and_extremes_port = processed_stage == QueryProcessingStage::Complete;
auto modified_query_ast = query_ast->clone();
if (has_virtual_shard_num_column)
@ -153,8 +162,11 @@ void SelectStreamFactory::createForShard(
auto source = std::make_shared<SourceFromInputStream>(std::move(stream), force_add_agg_info);
if (add_totals_port)
if (add_totals_and_extremes_port)
{
source->addTotalsPort();
source->addExtremesPort();
}
res.emplace_back(std::move(source));
};
@ -303,8 +315,11 @@ void SelectStreamFactory::createForShard(
auto lazy_stream = std::make_shared<LazyBlockInputStream>("LazyShardWithLocalReplica", header, lazily_create_stream);
auto source = std::make_shared<SourceFromInputStream>(std::move(lazy_stream), force_add_agg_info);
if (add_totals_port)
if (add_totals_and_extremes_port)
{
source->addTotalsPort();
source->addExtremesPort();
}
res.emplace_back(std::move(source));
}

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@ -87,7 +87,6 @@
#include <Processors/Transforms/MergingSortedTransform.h>
#include <Processors/Transforms/DistinctTransform.h>
#include <Processors/Transforms/LimitByTransform.h>
#include <Processors/Transforms/ExtremesTransform.h>
#include <Processors/Transforms/CreatingSetsTransform.h>
#include <Processors/Transforms/RollupTransform.h>
#include <Processors/Transforms/CubeTransform.h>
@ -2542,8 +2541,7 @@ void InterpreterSelectQuery::executeExtremes(QueryPipeline & pipeline)
if (!context->getSettingsRef().extremes)
return;
auto transform = std::make_shared<ExtremesTransform>(pipeline.getHeader());
pipeline.addExtremesTransform(std::move(transform));
pipeline.addExtremesTransform();
}

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@ -30,7 +30,10 @@ static void checkProcessorHasSingleOutput(IProcessor * processor)
/// Check tree invariants (described in TreeExecutor.h).
/// Collect sources with progress.
static void validateTree(const Processors & processors, IProcessor * root, IProcessor * totals_root, std::vector<ISourceWithProgress *> & sources)
static void validateTree(
const Processors & processors,
IProcessor * root, IProcessor * totals_root, IProcessor * extremes_root,
std::vector<ISourceWithProgress *> & sources)
{
std::unordered_map<IProcessor *, size_t> index;
@ -49,6 +52,8 @@ static void validateTree(const Processors & processors, IProcessor * root, IProc
stack.push(root);
if (totals_root)
stack.push(totals_root);
if (extremes_root)
stack.push(extremes_root);
while (!stack.empty())
{
@ -104,11 +109,15 @@ void TreeExecutorBlockInputStream::init()
root = &output_port.getProcessor();
IProcessor * totals_root = nullptr;
IProcessor * extremes_root = nullptr;
if (totals_port)
totals_root = &totals_port->getProcessor();
validateTree(processors, root, totals_root, sources_with_progress);
if (extremes_port)
extremes_root = &extremes_port->getProcessor();
validateTree(processors, root, totals_root, extremes_root, sources_with_progress);
input_port = std::make_unique<InputPort>(getHeader(), root);
connect(output_port, *input_port);
@ -121,15 +130,24 @@ void TreeExecutorBlockInputStream::init()
input_totals_port->setNeeded();
}
if (extremes_port)
{
input_extremes_port = std::make_unique<InputPort>(extremes_port->getHeader(), root);
connect(*extremes_port, *input_extremes_port);
input_extremes_port->setNeeded();
}
initRowsBeforeLimit();
}
void TreeExecutorBlockInputStream::execute(bool on_totals)
void TreeExecutorBlockInputStream::execute(bool on_totals, bool on_extremes)
{
std::stack<IProcessor *> stack;
if (on_totals)
stack.push(&totals_port->getProcessor());
else if (on_extremes)
stack.push(&extremes_port->getProcessor());
else
stack.push(root);
@ -283,11 +301,18 @@ Block TreeExecutorBlockInputStream::readImpl()
{
if (totals_port && !input_totals_port->isFinished())
{
execute(true);
execute(true, false);
if (input_totals_port->hasData())
totals = getHeader().cloneWithColumns(input_totals_port->pull().detachColumns());
}
if (extremes_port && !input_extremes_port->isFinished())
{
execute(false, true);
if (input_extremes_port->hasData())
extremes = getHeader().cloneWithColumns(input_extremes_port->pull().detachColumns());
}
if (rows_before_limit_at_least && rows_before_limit_at_least->hasAppliedLimit())
info.setRowsBeforeLimit(rows_before_limit_at_least->get());
@ -311,7 +336,7 @@ Block TreeExecutorBlockInputStream::readImpl()
return block;
}
execute(false);
execute(false, false);
}
}

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@ -31,6 +31,7 @@ public:
interpreter_context.emplace_back(context);
totals_port = pipe.getTotalsPort();
extremes_port = pipe.getExtremesPort();
processors = std::move(pipe).detachProcessors();
init();
}
@ -52,10 +53,12 @@ protected:
private:
OutputPort & output_port;
OutputPort * totals_port = nullptr;
OutputPort * extremes_port = nullptr;
Processors processors;
IProcessor * root = nullptr;
std::unique_ptr<InputPort> input_port;
std::unique_ptr<InputPort> input_totals_port;
std::unique_ptr<InputPort> input_extremes_port;
RowsBeforeLimitCounterPtr rows_before_limit_at_least;
/// Remember sources that support progress.
@ -65,7 +68,7 @@ private:
void init();
/// Execute tree step-by-step until root returns next chunk or execution is finished.
void execute(bool on_totals);
void execute(bool on_totals, bool on_extremes);
void initRowsBeforeLimit();

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@ -225,7 +225,7 @@ void PrettyBlockOutputFormat::consumeTotals(Chunk chunk)
{
total_rows = 0;
writeSuffixIfNot();
writeCString("\nExtremes:\n", out);
writeCString("\nTotals:\n", out);
write(chunk, PortKind::Totals);
}
@ -233,7 +233,7 @@ void PrettyBlockOutputFormat::consumeExtremes(Chunk chunk)
{
total_rows = 0;
writeSuffixIfNot();
writeCString("\nTotals:\n", out);
writeCString("\nExtremes:\n", out);
write(chunk, PortKind::Extremes);
}

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@ -1,9 +1,11 @@
#pragma once
#include <Processors/IProcessor.h>
#include <Processors/ISink.h>
namespace DB
{
/// Sink which closes input port and reads nothing.
class NullSink : public IProcessor
{
public:
@ -19,4 +21,15 @@ public:
InputPort & getPort() { return inputs.front(); }
};
/// Sink which reads everything and do nothing with it.
class EmptySink : public ISink
{
public:
explicit EmptySink(Block header) : ISink(std::move(header)) {}
String getName() const override { return "EmptySink"; }
protected:
void consume(Chunk) override {}
};
}

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@ -1,5 +1,6 @@
#include <Processors/Pipe.h>
#include <IO/WriteHelpers.h>
#include <Processors/Sources/SourceFromInputStream.h>
namespace DB
{
@ -48,7 +49,7 @@ static void checkSource(const IProcessor & source)
throw Exception("Source for pipe should have single output, but it doesn't have any",
ErrorCodes::LOGICAL_ERROR);
if (source.getOutputs().size() > 2)
if (source.getOutputs().size() > 1)
throw Exception("Source for pipe should have single or two outputs, but " + source.getName() + " has " +
toString(source.getOutputs().size()) + " outputs.", ErrorCodes::LOGICAL_ERROR);
}
@ -56,18 +57,22 @@ static void checkSource(const IProcessor & source)
Pipe::Pipe(ProcessorPtr source)
{
if (auto * source_from_input_stream = typeid_cast<SourceFromInputStream *>(source.get()))
{
totals = source_from_input_stream->getTotalsPort();
extremes = source_from_input_stream->getExtremesPort();
}
else if (source->getOutputs().size() != 1)
checkSource(*source);
output_port = &source->getOutputs().front();
if (source->getOutputs().size() > 1)
totals = &source->getOutputs().back();
output_port = &source->getOutputs().front();
processors.emplace_back(std::move(source));
max_parallel_streams = 1;
}
Pipe::Pipe(Processors processors_, OutputPort * output_port_, OutputPort * totals_)
: processors(std::move(processors_)), output_port(output_port_), totals(totals_)
Pipe::Pipe(Processors processors_, OutputPort * output_port_, OutputPort * totals_, OutputPort * extremes_)
: processors(std::move(processors_)), output_port(output_port_), totals(totals_), extremes(extremes_)
{
}

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@ -47,8 +47,11 @@ public:
void enableQuota();
/// Totals and extremes port.
void setTotalsPort(OutputPort * totals_) { totals = totals_; }
void setExtremesPort(OutputPort * extremes_) { extremes = extremes_; }
OutputPort * getTotalsPort() const { return totals; }
OutputPort * getExtremesPort() const { return extremes; }
size_t maxParallelStreams() const { return max_parallel_streams; }
@ -67,6 +70,7 @@ private:
Processors processors;
OutputPort * output_port = nullptr;
OutputPort * totals = nullptr;
OutputPort * extremes = nullptr;
/// It is the max number of processors which can be executed in parallel for each step. See QueryPipeline::Streams.
size_t max_parallel_streams = 0;
@ -84,7 +88,7 @@ private:
/// and therefore we can skip those checks.
/// Note that Pipe represents a tree if it was created using public interface. But this constructor can't assert it.
/// So, it's possible that TreeExecutorBlockInputStream could be unable to convert such Pipe to IBlockInputStream.
explicit Pipe(Processors processors_, OutputPort * output_port, OutputPort * totals);
explicit Pipe(Processors processors_, OutputPort * output_port, OutputPort * totals, OutputPort * extremes);
friend class QueryPipeline;
};

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@ -60,6 +60,58 @@ void QueryPipeline::init(Pipe pipe)
init(std::move(pipes));
}
static OutputPort * uniteExtremes(const std::vector<OutputPort *> & ports, const Block & header, Processors & processors)
{
/// Here we calculate extremes for extremes in case we unite several pipelines.
/// Example: select number from numbers(2) union all select number from numbers(3)
/// ->> Resize -> Extremes --(output port)----> Null
/// --(extremes port)--> ...
auto resize = std::make_shared<ResizeProcessor>(header, ports.size(), 1);
auto extremes = std::make_shared<ExtremesTransform>(header);
auto sink = std::make_shared<EmptySink>(header);
auto * extremes_port = &extremes->getExtremesPort();
auto in = resize->getInputs().begin();
for (auto & port : ports)
connect(*port, *(in++));
connect(resize->getOutputs().front(), extremes->getInputPort());
connect(extremes->getOutputPort(), sink->getPort());
processors.emplace_back(std::move(resize));
processors.emplace_back(std::move(extremes));
processors.emplace_back(std::move(sink));
return extremes_port;
}
static OutputPort * uniteTotals(const std::vector<OutputPort *> & ports, const Block & header, Processors & processors)
{
/// Calculate totals fro several streams.
/// Take totals from first sources which has any, skip others.
/// ->> Concat -> Limit
auto concat = std::make_shared<ConcatProcessor>(header, ports.size());
auto limit = std::make_shared<LimitTransform>(header, 1, 0);
auto * totals_port = &limit->getOutputPort();
auto in = concat->getInputs().begin();
for (auto & port : ports)
connect(*port, *(in++));
connect(concat->getOutputs().front(), limit->getInputPort());
processors.emplace_back(std::move(concat));
processors.emplace_back(std::move(limit));
return totals_port;
}
void QueryPipeline::init(Pipes pipes)
{
if (initialized())
@ -82,6 +134,7 @@ void QueryPipeline::init(Pipes pipes)
}
std::vector<OutputPort *> totals;
std::vector<OutputPort *> extremes;
for (auto & pipe : pipes)
{
@ -98,6 +151,12 @@ void QueryPipeline::init(Pipes pipes)
totals.emplace_back(totals_port);
}
if (auto * port = pipe.getExtremesPort())
{
assertBlocksHaveEqualStructure(current_header, port->getHeader(), "QueryPipeline");
extremes.emplace_back(port);
}
streams.addStream(&pipe.getPort(), pipe.maxParallelStreams());
auto cur_processors = std::move(pipe).detachProcessors();
processors.insert(processors.end(), cur_processors.begin(), cur_processors.end());
@ -108,15 +167,15 @@ void QueryPipeline::init(Pipes pipes)
if (totals.size() == 1)
totals_having_port = totals.back();
else
{
auto resize = std::make_shared<ResizeProcessor>(current_header, totals.size(), 1);
auto in = resize->getInputs().begin();
for (auto & total : totals)
connect(*total, *(in++));
totals_having_port = &resize->getOutputs().front();
processors.emplace_back(std::move(resize));
totals_having_port = uniteTotals(totals, current_header, processors);
}
if (!extremes.empty())
{
if (extremes.size() == 1)
extremes_port = extremes.back();
else
extremes_port = uniteExtremes(extremes, current_header, processors);
}
}
@ -356,31 +415,33 @@ void QueryPipeline::dropTotalsIfHas()
}
}
void QueryPipeline::addExtremesTransform(ProcessorPtr transform)
void QueryPipeline::addExtremesTransform()
{
checkInitialized();
if (!typeid_cast<const ExtremesTransform *>(transform.get()))
throw Exception("ExtremesTransform expected for QueryPipeline::addExtremesTransform.",
ErrorCodes::LOGICAL_ERROR);
if (extremes_port)
throw Exception("Extremes transform was already added to pipeline.", ErrorCodes::LOGICAL_ERROR);
if (getNumStreams() != 1)
throw Exception("Cant't add Extremes transform because pipeline is expected to have single stream, "
"but it has " + toString(getNumStreams()) + " streams.", ErrorCodes::LOGICAL_ERROR);
std::vector<OutputPort *> extremes;
extremes.reserve(streams.size());
connect(*streams.front(), transform->getInputs().front());
for (auto & stream : streams)
{
auto transform = std::make_shared<ExtremesTransform>(current_header);
connect(*stream, transform->getInputPort());
auto & outputs = transform->getOutputs();
stream = &transform->getOutputPort();
extremes.push_back(&transform->getExtremesPort());
streams.assign({ &outputs.front() });
extremes_port = &outputs.back();
current_header = outputs.front().getHeader();
processors.emplace_back(std::move(transform));
}
if (extremes.size() == 1)
extremes_port = extremes.front();
else
extremes_port = uniteExtremes(extremes, current_header, processors);
}
void QueryPipeline::addCreatingSetsTransform(ProcessorPtr transform)
{
checkInitialized();
@ -455,6 +516,13 @@ void QueryPipeline::unitePipelines(
});
std::vector<OutputPort *> extremes;
std::vector<OutputPort *> totals;
if (extremes_port)
extremes.push_back(extremes_port);
if (totals_having_port)
totals.push_back(totals_having_port);
for (auto & pipeline : pipelines)
{
@ -478,19 +546,14 @@ void QueryPipeline::unitePipelines(
/// Take totals only from first port.
if (pipeline.totals_having_port)
{
if (!totals_having_port)
{
auto converting = std::make_shared<ConvertingTransform>(
pipeline.current_header, common_header, ConvertingTransform::MatchColumnsMode::Position, context);
connect(*pipeline.totals_having_port, converting->getInputPort());
totals_having_port = &converting->getOutputPort();
totals.push_back(&converting->getOutputPort());
processors.push_back(std::move(converting));
}
else
pipeline.dropTotalsIfHas();
}
processors.insert(processors.end(), pipeline.processors.begin(), pipeline.processors.end());
streams.addStreams(pipeline.streams);
@ -504,28 +567,18 @@ void QueryPipeline::unitePipelines(
if (!extremes.empty())
{
size_t num_inputs = extremes.size() + (extremes_port ? 1u : 0u);
if (num_inputs == 1)
extremes_port = extremes.front();
if (extremes.size() == 1)
extremes_port = extremes.back();
else
{
/// Add extra processor for extremes.
auto resize = std::make_shared<ResizeProcessor>(current_header, num_inputs, 1);
auto input = resize->getInputs().begin();
if (extremes_port)
connect(*extremes_port, *(input++));
for (auto & output : extremes)
connect(*output, *(input++));
auto transform = std::make_shared<ExtremesTransform>(current_header);
extremes_port = &transform->getOutputPort();
connect(resize->getOutputs().front(), transform->getInputPort());
processors.emplace_back(std::move(transform));
extremes_port = uniteExtremes(extremes, current_header, processors);
}
if (!totals.empty())
{
if (totals.size() == 1)
totals_having_port = totals.back();
else
totals_having_port = uniteTotals(totals, current_header, processors);
}
}
@ -644,7 +697,7 @@ void QueryPipeline::initRowsBeforeLimit()
Pipe QueryPipeline::getPipe() &&
{
resize(1);
Pipe pipe(std::move(processors), streams.at(0), totals_having_port);
Pipe pipe(std::move(processors), streams.at(0), totals_having_port, extremes_port);
pipe.max_parallel_streams = streams.maxParallelStreams();
for (auto & lock : table_locks)
@ -659,6 +712,9 @@ Pipe QueryPipeline::getPipe() &&
if (totals_having_port)
pipe.setTotalsPort(totals_having_port);
if (extremes_port)
pipe.setExtremesPort(extremes_port);
return pipe;
}

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@ -99,7 +99,7 @@ public:
void addSimpleTransform(const ProcessorGetterWithStreamKind & getter);
void addPipe(Processors pipe);
void addTotalsHavingTransform(ProcessorPtr transform);
void addExtremesTransform(ProcessorPtr transform);
void addExtremesTransform();
void addCreatingSetsTransform(ProcessorPtr transform);
void setOutput(ProcessorPtr output);

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@ -28,11 +28,20 @@ void SourceFromInputStream::init()
void SourceFromInputStream::addTotalsPort()
{
if (has_totals_port)
if (totals_port)
throw Exception("Totals port was already added for SourceFromInputStream.", ErrorCodes::LOGICAL_ERROR);
outputs.emplace_back(outputs.front().getHeader(), this);
has_totals_port = true;
totals_port = &outputs.back();
}
void SourceFromInputStream::addExtremesPort()
{
if (extremes_port)
throw Exception("Extremes port was already added for SourceFromInputStream.", ErrorCodes::LOGICAL_ERROR);
outputs.emplace_back(outputs.front().getHeader(), this);
extremes_port = &outputs.back();
}
IProcessor::Status SourceFromInputStream::prepare()
@ -47,23 +56,32 @@ IProcessor::Status SourceFromInputStream::prepare()
if (!is_stream_finished && !isCancelled())
return Status::Ready;
if (has_totals_port)
if (totals_port && !totals_port->isFinished())
{
auto & totals_out = outputs.back();
if (totals_out.isFinished())
return Status::Finished;
if (has_totals)
{
if (!totals_out.canPush())
if (!totals_port->canPush())
return Status::PortFull;
totals_out.push(std::move(totals));
totals_port->push(std::move(totals));
has_totals = false;
}
totals_out.finish();
totals_port->finish();
}
if (extremes_port && !extremes_port->isFinished())
{
if (has_extremes)
{
if (!extremes_port->canPush())
return Status::PortFull;
extremes_port->push(std::move(extremes));
has_extremes = false;
}
extremes_port->finish();
}
}
@ -138,13 +156,22 @@ Chunk SourceFromInputStream::generate()
if (auto totals_block = stream->getTotals())
{
if (totals_block.rows() == 1) /// Sometimes we can get empty totals. Skip it.
if (totals_block.rows() > 0) /// Sometimes we can get empty totals. Skip it.
{
totals.setColumns(totals_block.getColumns(), 1);
totals.setColumns(totals_block.getColumns(), totals_block.rows());
has_totals = true;
}
}
if (auto extremes_block = stream->getExtremes())
{
if (extremes_block.rows() > 0) /// Sometimes we can get empty extremes. Skip it.
{
extremes.setColumns(extremes_block.getColumns(), extremes_block.rows());
has_extremes = true;
}
}
is_stream_finished = true;
return {};
}

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@ -23,6 +23,10 @@ public:
BlockInputStreamPtr & getStream() { return stream; }
void addTotalsPort();
void addExtremesPort();
OutputPort * getTotalsPort() const { return totals_port; }
OutputPort * getExtremesPort() const { return extremes_port; }
void setRowsBeforeLimitCounter(RowsBeforeLimitCounterPtr counter) { rows_before_limit.swap(counter); }
@ -44,9 +48,13 @@ private:
RowsBeforeLimitCounterPtr rows_before_limit;
Chunk totals;
bool has_totals_port = false;
OutputPort * totals_port = nullptr;
bool has_totals = false;
Chunk extremes;
OutputPort * extremes_port = nullptr;
bool has_extremes = false;
bool is_generating_finished = false;
bool is_stream_finished = false;
bool is_stream_started = false;

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@ -0,0 +1,110 @@
0
1
0
1
-
-
-
0
1
0
1
0
1
-
-
-
0
1
0
1
0
1
-
-
-
0
1
0
1
0
1
-
-
-
0
1
0
1
------
------
------
0
0
0
1
1
2
0
2
-
-
-
0
0
0
1
1
2
0
2
-
-
-
0
0
0
1
1
2
0
2
------
------
------
0
0
1
1
2
0
2
-
-
-
0
0
1
1
2
0
2

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@ -0,0 +1,55 @@
set send_logs_level = 'error';
set extremes = 1;
-- set experimental_use_processors=0;
select * from remote('127.0.0.1', numbers(2));
select '-';
select * from remote('127.0.0.{1,1}', numbers(2));
select '-';
select * from remote('127.0.0.{1,2}', numbers(2));
select '-';
select * from remote('127.0.0.{2,2}', numbers(2));
select '-';
select * from remote('127.0.0.2', numbers(2));
select '------';
select * from (select * from numbers(2) union all select * from numbers(3) union all select * from numbers(1)) order by number;
select '-';
select * from (select * from numbers(1) union all select * from numbers(2) union all select * from numbers(3)) order by number;
select '-';
select * from (select * from numbers(3) union all select * from numbers(1) union all select * from numbers(2)) order by number;
select '------';
create database if not exists shard_0;
create database if not exists shard_1;
drop table if exists shard_0.num_01232;
drop table if exists shard_0.num2_01232;
drop table if exists shard_1.num_01232;
drop table if exists shard_1.num2_01232;
drop table if exists distr;
drop table if exists distr2;
create table shard_0.num_01232 (number UInt64) engine = MergeTree order by number;
create table shard_1.num_01232 (number UInt64) engine = MergeTree order by number;
insert into shard_0.num_01232 select number from numbers(2);
insert into shard_1.num_01232 select number from numbers(3);
create table distr (number UInt64) engine = Distributed(test_cluster_two_shards_different_databases, '', num_01232);
create table shard_0.num2_01232 (number UInt64) engine = MergeTree order by number;
create table shard_1.num2_01232 (number UInt64) engine = MergeTree order by number;
insert into shard_0.num2_01232 select number from numbers(3);
insert into shard_1.num2_01232 select number from numbers(2);
create table distr2 (number UInt64) engine = Distributed(test_cluster_two_shards_different_databases, '', num2_01232);
select * from distr order by number;
select '-';
select * from distr2 order by number;
drop table if exists shard_0.num_01232;
drop table if exists shard_0.num2_01232;
drop table if exists shard_1.num_01232;
drop table if exists shard_1.num2_01232;
drop table if exists distr;
drop table if exists distr2;