ClickHouse/dbms/src/Dictionaries/DictionarySourceFactory.cpp
Vitaly Baranov b4384ce2a9 Dictionaries can be loaded in parallel.
A bad dictionary cannot block all the loading anymore.
Implemented really lazy loading of external dictionaries.
Provided more detailed information about the loading of each dictionary
to make diagnostics easier.
2019-06-14 22:18:47 +03:00

105 lines
3.3 KiB
C++

#include "DictionarySourceFactory.h"
#include <Columns/ColumnsNumber.h>
#include <Core/Block.h>
#include <Core/ColumnWithTypeAndName.h>
#include <DataTypes/DataTypeNullable.h>
#include <DataTypes/DataTypesNumber.h>
#include <Poco/Logger.h>
#include <common/logger_useful.h>
#include "DictionaryStructure.h"
namespace DB
{
namespace ErrorCodes
{
extern const int UNKNOWN_ELEMENT_IN_CONFIG;
extern const int EXCESSIVE_ELEMENT_IN_CONFIG;
extern const int LOGICAL_ERROR;
extern const int SUPPORT_IS_DISABLED;
}
namespace
{
Block createSampleBlock(const DictionaryStructure & dict_struct)
{
Block block;
if (dict_struct.id)
block.insert(ColumnWithTypeAndName{ColumnUInt64::create(1, 0), std::make_shared<DataTypeUInt64>(), dict_struct.id->name});
if (dict_struct.key)
{
for (const auto & attribute : *dict_struct.key)
{
auto column = attribute.type->createColumn();
column->insertDefault();
block.insert(ColumnWithTypeAndName{std::move(column), attribute.type, attribute.name});
}
}
if (dict_struct.range_min)
{
for (const auto & attribute : {dict_struct.range_min, dict_struct.range_max})
{
const auto & type = std::make_shared<DataTypeNullable>(attribute->type);
auto column = type->createColumn();
column->insertDefault();
block.insert(ColumnWithTypeAndName{std::move(column), type, attribute->name});
}
}
for (const auto & attribute : dict_struct.attributes)
{
auto column = attribute.type->createColumn();
column->insert(attribute.null_value);
block.insert(ColumnWithTypeAndName{std::move(column), attribute.type, attribute.name});
}
return block;
}
}
DictionarySourceFactory::DictionarySourceFactory() : log(&Poco::Logger::get("DictionarySourceFactory"))
{
}
void DictionarySourceFactory::registerSource(const std::string & source_type, Creator create_source)
{
if (!registered_sources.emplace(source_type, std::move(create_source)).second)
throw Exception("DictionarySourceFactory: the source name '" + source_type + "' is not unique", ErrorCodes::LOGICAL_ERROR);
}
DictionarySourcePtr DictionarySourceFactory::create(
const std::string & name,
const Poco::Util::AbstractConfiguration & config,
const std::string & config_prefix,
const DictionaryStructure & dict_struct,
Context & context) const
{
Poco::Util::AbstractConfiguration::Keys keys;
config.keys(config_prefix, keys);
if (keys.size() != 1)
throw Exception{name + ": element dictionary.source should have exactly one child element",
ErrorCodes::EXCESSIVE_ELEMENT_IN_CONFIG};
const auto & source_type = keys.front();
const auto found = registered_sources.find(source_type);
if (found != registered_sources.end())
{
const auto & create_source = found->second;
auto sample_block = createSampleBlock(dict_struct);
return create_source(dict_struct, config, config_prefix, sample_block, context);
}
throw Exception{name + ": unknown dictionary source type: " + source_type, ErrorCodes::UNKNOWN_ELEMENT_IN_CONFIG};
}
}