Merge remote-tracking branch 'upstream/master' into fix25

This commit is contained in:
proller 2019-07-17 12:17:03 +03:00
commit 17dd579dac
22 changed files with 161 additions and 83 deletions

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@ -13,6 +13,6 @@ ClickHouse is an open-source column-oriented database management system that all
* You can also [fill this form](https://forms.yandex.com/surveys/meet-yandex-clickhouse-team/) to meet Yandex ClickHouse team in person.
## Upcoming Events
* [ClickHouse Meetup in Minsk](https://yandex.ru/promo/metrica/clickhouse-minsk) on July 11.
* [ClickHouse Meetup in Saint Petersburg](https://yandex.ru/promo/clickhouse/saint-petersburg-2019) on July 27.
* [ClickHouse Meetup in Shenzhen](https://www.huodongxing.com/event/3483759917300) on October 20.
* [ClickHouse Meetup in Shanghai](https://www.huodongxing.com/event/4483760336000) on October 27.

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@ -14,10 +14,15 @@ std::vector<XMLConfigurationPtr> ConfigPreprocessor::processConfig(
{
std::vector<XMLConfigurationPtr> result;
for (const auto & path : paths)
for (const auto & path_str : paths)
{
result.emplace_back(XMLConfigurationPtr(new XMLConfiguration(path)));
result.back()->setString("path", Poco::Path(path).absolute().toString());
auto test = XMLConfigurationPtr(new XMLConfiguration(path_str));
result.push_back(test);
const auto path = Poco::Path(path_str);
test->setString("path", path.absolute().toString());
if (test->getString("name", "") == "")
test->setString("name", path.getBaseName());
}
/// Leave tests:

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@ -3,6 +3,7 @@
#include <Core/Types.h>
#include <Common/CpuId.h>
#include <common/getMemoryAmount.h>
#include <DataStreams/RemoteBlockInputStream.h>
#include <IO/ConnectionTimeouts.h>
#include <IO/ReadBufferFromFile.h>
#include <IO/ReadHelpers.h>
@ -296,6 +297,47 @@ void PerformanceTest::runQueries(
break;
}
}
if (got_SIGINT)
{
return;
}
// Pull memory usage data from query log. The log is normally filled in
// background, so we have to flush it synchronously here to see all the
// previous queries.
{
RemoteBlockInputStream flush_log(connection, "system flush logs",
{} /* header */, context);
flush_log.readPrefix();
while (flush_log.read());
flush_log.readSuffix();
}
for (auto & statistics : statistics_by_run)
{
RemoteBlockInputStream log_reader(connection,
"select memory_usage from system.query_log where type = 2 and query_id = '"
+ statistics.query_id + "'",
{} /* header */, context);
log_reader.readPrefix();
Block block = log_reader.read();
if (block.columns() == 0)
{
LOG_WARNING(log, "Query '" << statistics.query_id << "' is not found in query log.");
continue;
}
assert(block.columns() == 1);
assert(block.getDataTypes()[0]->getName() == "UInt64");
ColumnPtr column = block.getByPosition(0).column;
assert(column->size() == 1);
StringRef ref = column->getDataAt(0);
assert(ref.size == sizeof(UInt64));
statistics.memory_usage = *reinterpret_cast<const UInt64*>(ref.data);
log_reader.readSuffix();
}
}

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@ -260,15 +260,12 @@ static std::vector<std::string> getInputFiles(const po::variables_map & options,
if (input_files.empty())
throw DB::Exception("Did not find any xml files", DB::ErrorCodes::BAD_ARGUMENTS);
else
LOG_INFO(log, "Found " << input_files.size() << " files");
}
else
{
input_files = options["input-files"].as<std::vector<std::string>>();
LOG_INFO(log, "Found " + std::to_string(input_files.size()) + " input files");
std::vector<std::string> collected_files;
std::vector<std::string> collected_files;
for (const std::string & filename : input_files)
{
fs::path file(filename);
@ -290,6 +287,8 @@ static std::vector<std::string> getInputFiles(const po::variables_map & options,
input_files = std::move(collected_files);
}
LOG_INFO(log, "Found " + std::to_string(input_files.size()) + " input files");
std::sort(input_files.begin(), input_files.end());
return input_files;
}

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@ -157,6 +157,8 @@ std::string ReportBuilder::buildFullReport(
runJSON.set("avg_bytes_per_second", statistics.avg_bytes_speed_value);
}
runJSON.set("memory_usage", statistics.memory_usage);
run_infos.push_back(runJSON);
}
}

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@ -19,6 +19,7 @@ struct TestStats
Stopwatch avg_bytes_speed_watch;
bool last_query_was_cancelled = false;
std::string query_id;
size_t queries = 0;
@ -49,6 +50,8 @@ struct TestStats
size_t number_of_rows_speed_info_batches = 0;
size_t number_of_bytes_speed_info_batches = 0;
UInt64 memory_usage = 0;
bool ready = false; // check if a query wasn't interrupted by SIGINT
std::string exception;

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@ -2,9 +2,11 @@
#include <IO/Progress.h>
#include <DataStreams/RemoteBlockInputStream.h>
#include <Core/Block.h>
#include <Poco/UUIDGenerator.h>
namespace DB
{
namespace
{
@ -36,7 +38,7 @@ void checkFulfilledConditionsAndUpdate(
}
}
}
} // anonymous namespace
void executeQuery(
Connection & connection,
@ -47,12 +49,18 @@ void executeQuery(
Context & context,
const Settings & settings)
{
static const std::string query_id_prefix
= Poco::UUIDGenerator::defaultGenerator().create().toString() + "-";
static int next_query_id = 1;
statistics.watch_per_query.restart();
statistics.last_query_was_cancelled = false;
statistics.last_query_rows_read = 0;
statistics.last_query_bytes_read = 0;
statistics.query_id = query_id_prefix + std::to_string(next_query_id++);
RemoteBlockInputStream stream(connection, query, {}, context, &settings);
stream.setQueryId(statistics.query_id);
stream.setProgressCallback(
[&](const Progress & value)
@ -70,4 +78,5 @@ void executeQuery(
statistics.setTotalTime();
}
}

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@ -331,7 +331,8 @@ struct Settings : public SettingsCollection<Settings>
M(SettingBool, allow_hyperscan, true, "Allow functions that use Hyperscan library. Disable to avoid potentially long compilation times and excessive resource usage.") \
M(SettingBool, allow_simdjson, true, "Allow using simdjson library in 'JSON*' functions if AVX2 instructions are available. If disabled rapidjson will be used.") \
\
M(SettingUInt64, max_partitions_per_insert_block, 100, "Limit maximum number of partitions in single INSERTed block. Zero means unlimited. Throw exception if the block contains too many partitions. This setting is a safety threshold, because using large number of partitions is a common misconception.")
M(SettingUInt64, max_partitions_per_insert_block, 100, "Limit maximum number of partitions in single INSERTed block. Zero means unlimited. Throw exception if the block contains too many partitions. This setting is a safety threshold, because using large number of partitions is a common misconception.") \
M(SettingBool, check_query_single_value_result, true, "Return check query result as single 1/0 value")
DECLARE_SETTINGS_COLLECTION(LIST_OF_SETTINGS)

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@ -292,7 +292,7 @@ void RemoteBlockInputStream::sendQuery()
established = true;
auto timeouts = ConnectionTimeouts::getTCPTimeoutsWithFailover(settings);
multiplexed_connections->sendQuery(timeouts, query, "", stage, &context.getClientInfo(), true);
multiplexed_connections->sendQuery(timeouts, query, query_id, stage, &context.getClientInfo(), true);
established = false;
sent_query = true;

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@ -46,6 +46,11 @@ public:
~RemoteBlockInputStream() override;
/// Set the query_id. For now, used by performance test to later find the query
/// in the server query_log. Must be called before sending the query to the
/// server.
void setQueryId(const std::string& query_id_) { assert(!sent_query); query_id = query_id_; }
/// Specify how we allocate connections on a shard.
void setPoolMode(PoolMode pool_mode_) { pool_mode = pool_mode_; }
@ -95,6 +100,7 @@ private:
std::unique_ptr<MultiplexedConnections> multiplexed_connections;
const String query;
String query_id = "";
Context context;
/// Temporary tables needed to be sent to remote servers

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@ -7,6 +7,7 @@
#include <DataTypes/DataTypeString.h>
#include <Columns/ColumnsNumber.h>
#include <Common/typeid_cast.h>
#include <algorithm>
namespace DB
@ -42,22 +43,33 @@ BlockIO InterpreterCheckQuery::execute()
StoragePtr table = context.getTable(database_name, table_name);
auto check_results = table->checkData(query_ptr, context);
auto block_structure = getBlockStructure();
auto path_column = block_structure[0].type->createColumn();
auto is_passed_column = block_structure[1].type->createColumn();
auto message_column = block_structure[2].type->createColumn();
for (const auto & check_result : check_results)
Block block;
if (context.getSettingsRef().check_query_single_value_result)
{
path_column->insert(check_result.fs_path);
is_passed_column->insert(static_cast<UInt8>(check_result.success));
message_column->insert(check_result.failure_message);
bool result = std::all_of(check_results.begin(), check_results.end(), [] (const CheckResult & res) { return res.success; });
auto column = ColumnUInt8::create();
column->insertValue(UInt64(result));
block = Block{{std::move(column), std::make_shared<DataTypeUInt8>(), "result"}};
}
else
{
auto block_structure = getBlockStructure();
auto path_column = block_structure[0].type->createColumn();
auto is_passed_column = block_structure[1].type->createColumn();
auto message_column = block_structure[2].type->createColumn();
Block block({
{std::move(path_column), block_structure[0].type, block_structure[0].name},
{std::move(is_passed_column), block_structure[1].type, block_structure[1].name},
{std::move(message_column), block_structure[2].type, block_structure[2].name}});
for (const auto & check_result : check_results)
{
path_column->insert(check_result.fs_path);
is_passed_column->insert(static_cast<UInt8>(check_result.success));
message_column->insert(check_result.failure_message);
}
block = Block({
{std::move(path_column), block_structure[0].type, block_structure[0].name},
{std::move(is_passed_column), block_structure[1].type, block_structure[1].name},
{std::move(message_column), block_structure[2].type, block_structure[2].name}});
}
BlockIO res;
res.in = std::make_shared<OneBlockInputStream>(block);

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@ -21,7 +21,6 @@ private:
ASTPtr query_ptr;
const Context & context;
Block result;
};
}

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@ -49,7 +49,17 @@ static void likeStringToBloomFilter(
while (cur < data.size() && token_extractor->nextLike(data, &cur, token))
bloom_filter.add(token.c_str(), token.size());
}
/// Unified condition for equals, startsWith and endsWith
bool MergeTreeConditionFullText::createFunctionEqualsCondition(RPNElement & out, const Field & value, const MergeTreeIndexFullText & idx)
{
out.function = RPNElement::FUNCTION_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
idx.bloom_filter_size, idx.bloom_filter_hashes, idx.seed);
const auto & str = value.get<String>();
stringToBloomFilter(str.c_str(), str.size(), idx.token_extractor_func, *out.bloom_filter);
return true;
}
MergeTreeIndexGranuleFullText::MergeTreeIndexGranuleFullText(const MergeTreeIndexFullText & index)
: IMergeTreeIndexGranule()
@ -129,13 +139,7 @@ const MergeTreeConditionFullText::AtomMap MergeTreeConditionFullText::atom_map
"equals",
[] (RPNElement & out, const Field & value, const MergeTreeIndexFullText & idx)
{
out.function = RPNElement::FUNCTION_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
idx.bloom_filter_size, idx.bloom_filter_hashes, idx.seed);
const auto & str = value.get<String>();
stringToBloomFilter(str.c_str(), str.size(), idx.token_extractor_func, *out.bloom_filter);
return true;
return createFunctionEqualsCondition(out, value, idx);
}
},
{
@ -168,26 +172,14 @@ const MergeTreeConditionFullText::AtomMap MergeTreeConditionFullText::atom_map
"startsWith",
[] (RPNElement & out, const Field & value, const MergeTreeIndexFullText & idx)
{
out.function = RPNElement::FUNCTION_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
idx.bloom_filter_size, idx.bloom_filter_hashes, idx.seed);
const auto & prefix = value.get<String>();
stringToBloomFilter(prefix.c_str(), prefix.size(), idx.token_extractor_func, *out.bloom_filter);
return true;
return createFunctionEqualsCondition(out, value, idx);
}
},
{
"endsWith",
[] (RPNElement & out, const Field & value, const MergeTreeIndexFullText & idx)
{
out.function = RPNElement::FUNCTION_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
idx.bloom_filter_size, idx.bloom_filter_hashes, idx.seed);
const auto & suffix = value.get<String>();
stringToBloomFilter(suffix.c_str(), suffix.size(), idx.token_extractor_func, *out.bloom_filter);
return true;
return createFunctionEqualsCondition(out, value, idx);
}
},
{
@ -196,6 +188,7 @@ const MergeTreeConditionFullText::AtomMap MergeTreeConditionFullText::atom_map
{
out.function = RPNElement::FUNCTION_MULTI_SEARCH;
/// 2d vector is not needed here but is used because already exists for FUNCTION_IN
std::vector<std::vector<BloomFilter>> bloom_filters;
bloom_filters.emplace_back();
for (const auto & element : value.get<Array>())
@ -405,7 +398,7 @@ bool MergeTreeConditionFullText::atomFromAST(
size_t key_arg_pos; /// Position of argument with key column (non-const argument)
size_t key_column_num = -1; /// Number of a key column (inside key_column_names array)
std::string func_name = func->name;
const auto & func_name = func->name;
if (functionIsInOrGlobalInOperator(func_name) && tryPrepareSetBloomFilter(args, out))
{

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@ -117,6 +117,8 @@ private:
bool getKey(const ASTPtr & node, size_t & key_column_num);
bool tryPrepareSetBloomFilter(const ASTs & args, RPNElement & out);
static bool createFunctionEqualsCondition(RPNElement & out, const Field & value, const MergeTreeIndexFullText & idx);
static const AtomMap atom_map;
const MergeTreeIndexFullText & index;

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@ -50,35 +50,35 @@ def remove_part_from_disk(node, table, part_name):
def test_check_normal_table_corruption(started_cluster):
node1.query("INSERT INTO non_replicated_mt VALUES (toDate('2019-02-01'), 1, 10), (toDate('2019-02-01'), 2, 12)")
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201902") == "201902_1_1_0\t1\t\n"
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201902", settings={"check_query_single_value_result": 0}) == "201902_1_1_0\t1\t\n"
remove_checksums_on_disk(node1, "non_replicated_mt", "201902_1_1_0")
assert node1.query("CHECK TABLE non_replicated_mt").strip() == "201902_1_1_0\t1\tChecksums recounted and written to disk."
assert node1.query("CHECK TABLE non_replicated_mt", settings={"check_query_single_value_result": 0}).strip() == "201902_1_1_0\t1\tChecksums recounted and written to disk."
assert node1.query("SELECT COUNT() FROM non_replicated_mt") == "2\n"
remove_checksums_on_disk(node1, "non_replicated_mt", "201902_1_1_0")
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201902").strip() == "201902_1_1_0\t1\tChecksums recounted and written to disk."
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201902", settings={"check_query_single_value_result": 0}).strip() == "201902_1_1_0\t1\tChecksums recounted and written to disk."
assert node1.query("SELECT COUNT() FROM non_replicated_mt") == "2\n"
corrupt_data_part_on_disk(node1, "non_replicated_mt", "201902_1_1_0")
assert node1.query("CHECK TABLE non_replicated_mt").strip() == "201902_1_1_0\t0\tCannot read all data. Bytes read: 2. Bytes expected: 16."
assert node1.query("CHECK TABLE non_replicated_mt", settings={"check_query_single_value_result": 0}).strip() == "201902_1_1_0\t0\tCannot read all data. Bytes read: 2. Bytes expected: 16."
assert node1.query("CHECK TABLE non_replicated_mt").strip() == "201902_1_1_0\t0\tCannot read all data. Bytes read: 2. Bytes expected: 16."
assert node1.query("CHECK TABLE non_replicated_mt", settings={"check_query_single_value_result": 0}).strip() == "201902_1_1_0\t0\tCannot read all data. Bytes read: 2. Bytes expected: 16."
node1.query("INSERT INTO non_replicated_mt VALUES (toDate('2019-01-01'), 1, 10), (toDate('2019-01-01'), 2, 12)")
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201901") == "201901_2_2_0\t1\t\n"
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "201901_2_2_0\t1\t\n"
corrupt_data_part_on_disk(node1, "non_replicated_mt", "201901_2_2_0")
remove_checksums_on_disk(node1, "non_replicated_mt", "201901_2_2_0")
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201901") == "201901_2_2_0\t0\tCheck of part finished with error: \\'Cannot read all data. Bytes read: 2. Bytes expected: 16.\\'\n"
assert node1.query("CHECK TABLE non_replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "201901_2_2_0\t0\tCheck of part finished with error: \\'Cannot read all data. Bytes read: 2. Bytes expected: 16.\\'\n"
def test_check_replicated_table_simple(started_cluster):
@ -90,16 +90,16 @@ def test_check_replicated_table_simple(started_cluster):
assert node1.query("SELECT count() from replicated_mt") == "2\n"
assert node2.query("SELECT count() from replicated_mt") == "2\n"
assert node1.query("CHECK TABLE replicated_mt") == "201902_0_0_0\t1\t\n"
assert node2.query("CHECK TABLE replicated_mt") == "201902_0_0_0\t1\t\n"
assert node1.query("CHECK TABLE replicated_mt", settings={"check_query_single_value_result": 0}) == "201902_0_0_0\t1\t\n"
assert node2.query("CHECK TABLE replicated_mt", settings={"check_query_single_value_result": 0}) == "201902_0_0_0\t1\t\n"
node2.query("INSERT INTO replicated_mt VALUES (toDate('2019-01-02'), 3, 10), (toDate('2019-01-02'), 4, 12)")
node1.query("SYSTEM SYNC REPLICA replicated_mt")
assert node1.query("SELECT count() from replicated_mt") == "4\n"
assert node2.query("SELECT count() from replicated_mt") == "4\n"
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901") == "201901_0_0_0\t1\t\n"
assert node2.query("CHECK TABLE replicated_mt PARTITION 201901") == "201901_0_0_0\t1\t\n"
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "201901_0_0_0\t1\t\n"
assert node2.query("CHECK TABLE replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "201901_0_0_0\t1\t\n"
def test_check_replicated_table_corruption(started_cluster):
@ -115,15 +115,15 @@ def test_check_replicated_table_corruption(started_cluster):
part_name = node1.query("SELECT name from system.parts where table = 'replicated_mt' and partition_id = '201901' and active = 1").strip()
corrupt_data_part_on_disk(node1, "replicated_mt", part_name)
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901") == "{p}\t0\tPart {p} looks broken. Removing it and queueing a fetch.\n".format(p=part_name)
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "{p}\t0\tPart {p} looks broken. Removing it and queueing a fetch.\n".format(p=part_name)
node1.query("SYSTEM SYNC REPLICA replicated_mt")
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901") == "{}\t1\t\n".format(part_name)
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "{}\t1\t\n".format(part_name)
assert node1.query("SELECT count() from replicated_mt") == "4\n"
remove_part_from_disk(node2, "replicated_mt", part_name)
assert node2.query("CHECK TABLE replicated_mt PARTITION 201901") == "{p}\t0\tPart {p} looks broken. Removing it and queueing a fetch.\n".format(p=part_name)
assert node2.query("CHECK TABLE replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "{p}\t0\tPart {p} looks broken. Removing it and queueing a fetch.\n".format(p=part_name)
node1.query("SYSTEM SYNC REPLICA replicated_mt")
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901") == "{}\t1\t\n".format(part_name)
assert node1.query("CHECK TABLE replicated_mt PARTITION 201901", settings={"check_query_single_value_result": 0}) == "{}\t1\t\n".format(part_name)
assert node1.query("SELECT count() from replicated_mt") == "4\n"

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@ -1,5 +1,2 @@
N.bin 1
S.bin 1
N.bin 1
S.bin 1
__marks.mrk 1
1
1

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@ -1,3 +1,5 @@
SET check_query_single_value_result = 1;
DROP TABLE IF EXISTS check_query_tiny_log;
CREATE TABLE check_query_tiny_log (N UInt32, S String) Engine = TinyLog;

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@ -1,3 +1,4 @@
SET check_query_single_value_result = 0;
DROP TABLE IF EXISTS mt_table;
CREATE TABLE mt_table (d Date, key UInt64, data String) ENGINE = MergeTree() PARTITION BY toYYYYMM(d) ORDER BY key;

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@ -1,17 +1,10 @@
1
1
1
8873898 12457120258355519194
8873898 12457120258355519194
8873898 12457120258355519194
8873898 12457120258355519194
AdvEngineID.bin 1
CounterID.bin 1
RegionID.bin 1
SearchPhrase.bin 1
UserID.bin 1
__marks.mrk 1
AdvEngineID.bin 1
CounterID.bin 1
RegionID.bin 1
SearchPhrase.bin 1
UserID.bin 1
data.bin 1
index.mrk 1
1
1
1

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@ -1,3 +1,5 @@
SET check_query_single_value_result = 1;
DROP TABLE IF EXISTS test.hits_log;
DROP TABLE IF EXISTS test.hits_tinylog;
DROP TABLE IF EXISTS test.hits_stripelog;

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@ -226,12 +226,22 @@ function make_rpm {
PACKAGE=clickhouse-server
ARCH=all
TARGET=noarch
unpack_pack
deb_unpack
mv ${PACKAGE}-$VERSION_FULL-2.spec ${PACKAGE}-$VERSION_FULL-2.spec_tmp
echo "Requires: clickhouse-common-static = $VERSION_FULL-2" >> ${PACKAGE}-$VERSION_FULL-2.spec
echo "Requires: tzdata" >> ${PACKAGE}-$VERSION_FULL-2.spec
echo "Requires: initscripts" >> ${PACKAGE}-$VERSION_FULL-2.spec
cat ${PACKAGE}-$VERSION_FULL-2.spec_tmp >> ${PACKAGE}-$VERSION_FULL-2.spec
rpm_pack
PACKAGE=clickhouse-client
ARCH=all
TARGET=noarch
unpack_pack
deb_unpack
mv ${PACKAGE}-$VERSION_FULL-2.spec ${PACKAGE}-$VERSION_FULL-2.spec_tmp
echo "Requires: clickhouse-common-static = $VERSION_FULL-2" >> ${PACKAGE}-$VERSION_FULL-2.spec
cat ${PACKAGE}-$VERSION_FULL-2.spec_tmp >> ${PACKAGE}-$VERSION_FULL-2.spec
rpm_pack
PACKAGE=clickhouse-test
ARCH=all

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@ -94,7 +94,7 @@
</div>
<div id="announcement" class="colored-block">
<div class="page">
Upcoming Meetups: <a class="announcement-link" href="https://yandex.ru/promo/metrica/clickhouse-minsk" rel="external nofollow" target="_blank">Minsk</a> on July 11 and <a class="announcement-link" href="https://www.huodongxing.com/event/3483759917300" rel="external nofollow" target="_blank">Shenzhen</a> on October 20
Upcoming Meetups: <a class="announcement-link" href="https://yandex.ru/promo/clickhouse/saint-petersburg-2019" rel="external nofollow" target="_blank">Saint Petersburg</a> on July 27 and <a class="announcement-link" href="https://www.huodongxing.com/event/3483759917300" rel="external nofollow" target="_blank">Shenzhen</a> on October 20
</div>
</div>
<div class="page">