ClickHouse/programs/copier/Internals.cpp
2020-10-10 02:31:33 +03:00

284 lines
9.6 KiB
C++

#include "Internals.h"
#include <Storages/MergeTree/MergeTreeData.h>
#include <Storages/extractKeyExpressionList.h>
namespace DB
{
namespace ErrorCodes
{
extern const int BAD_ARGUMENTS;
}
using ConfigurationPtr = Poco::AutoPtr<Poco::Util::AbstractConfiguration>;
ConfigurationPtr getConfigurationFromXMLString(const std::string & xml_data)
{
std::stringstream ss(xml_data);
Poco::XML::InputSource input_source{ss};
return {new Poco::Util::XMLConfiguration{&input_source}};
}
String getQuotedTable(const String & database, const String & table)
{
if (database.empty())
return backQuoteIfNeed(table);
return backQuoteIfNeed(database) + "." + backQuoteIfNeed(table);
}
String getQuotedTable(const DatabaseAndTableName & db_and_table)
{
return getQuotedTable(db_and_table.first, db_and_table.second);
}
// Creates AST representing 'ENGINE = Distributed(cluster, db, table, [sharding_key])
std::shared_ptr<ASTStorage> createASTStorageDistributed(
const String & cluster_name, const String & database, const String & table,
const ASTPtr & sharding_key_ast)
{
auto args = std::make_shared<ASTExpressionList>();
args->children.emplace_back(std::make_shared<ASTLiteral>(cluster_name));
args->children.emplace_back(std::make_shared<ASTIdentifier>(database));
args->children.emplace_back(std::make_shared<ASTIdentifier>(table));
if (sharding_key_ast)
args->children.emplace_back(sharding_key_ast);
auto engine = std::make_shared<ASTFunction>();
engine->name = "Distributed";
engine->arguments = args;
auto storage = std::make_shared<ASTStorage>();
storage->set(storage->engine, engine);
return storage;
}
BlockInputStreamPtr squashStreamIntoOneBlock(const BlockInputStreamPtr & stream)
{
return std::make_shared<SquashingBlockInputStream>(
stream,
std::numeric_limits<size_t>::max(),
std::numeric_limits<size_t>::max());
}
Block getBlockWithAllStreamData(const BlockInputStreamPtr & stream)
{
return squashStreamIntoOneBlock(stream)->read();
}
bool isExtendedDefinitionStorage(const ASTPtr & storage_ast)
{
const auto & storage = storage_ast->as<ASTStorage &>();
return storage.partition_by || storage.order_by || storage.sample_by;
}
ASTPtr extractPartitionKey(const ASTPtr & storage_ast)
{
String storage_str = queryToString(storage_ast);
const auto & storage = storage_ast->as<ASTStorage &>();
const auto & engine = storage.engine->as<ASTFunction &>();
if (!endsWith(engine.name, "MergeTree"))
{
throw Exception(
"Unsupported engine was specified in " + storage_str + ", only *MergeTree engines are supported",
ErrorCodes::BAD_ARGUMENTS);
}
if (isExtendedDefinitionStorage(storage_ast))
{
if (storage.partition_by)
return storage.partition_by->clone();
static const char * all = "all";
return std::make_shared<ASTLiteral>(Field(all, strlen(all)));
}
else
{
bool is_replicated = startsWith(engine.name, "Replicated");
size_t min_args = is_replicated ? 3 : 1;
if (!engine.arguments)
throw Exception("Expected arguments in " + storage_str, ErrorCodes::BAD_ARGUMENTS);
ASTPtr arguments_ast = engine.arguments->clone();
ASTs & arguments = arguments_ast->children;
if (arguments.size() < min_args)
throw Exception("Expected at least " + toString(min_args) + " arguments in " + storage_str,
ErrorCodes::BAD_ARGUMENTS);
ASTPtr & month_arg = is_replicated ? arguments[2] : arguments[1];
return makeASTFunction("toYYYYMM", month_arg->clone());
}
}
ASTPtr extractPrimaryKey(const ASTPtr & storage_ast)
{
String storage_str = queryToString(storage_ast);
const auto & storage = storage_ast->as<ASTStorage &>();
const auto & engine = storage.engine->as<ASTFunction &>();
if (!endsWith(engine.name, "MergeTree"))
{
throw Exception("Unsupported engine was specified in " + storage_str + ", only *MergeTree engines are supported",
ErrorCodes::BAD_ARGUMENTS);
}
if (!isExtendedDefinitionStorage(storage_ast))
{
throw Exception("Is not extended deginition storage " + storage_str + " Will be fixed later.",
ErrorCodes::BAD_ARGUMENTS);
}
if (storage.primary_key)
return storage.primary_key->clone();
return nullptr;
}
ASTPtr extractOrderBy(const ASTPtr & storage_ast)
{
String storage_str = queryToString(storage_ast);
const auto & storage = storage_ast->as<ASTStorage &>();
const auto & engine = storage.engine->as<ASTFunction &>();
if (!endsWith(engine.name, "MergeTree"))
{
throw Exception("Unsupported engine was specified in " + storage_str + ", only *MergeTree engines are supported",
ErrorCodes::BAD_ARGUMENTS);
}
if (!isExtendedDefinitionStorage(storage_ast))
{
throw Exception("Is not extended deginition storage " + storage_str + " Will be fixed later.",
ErrorCodes::BAD_ARGUMENTS);
}
if (storage.order_by)
return storage.order_by->clone();
throw Exception("ORDER BY cannot be empty", ErrorCodes::BAD_ARGUMENTS);
}
/// Wraps only identifiers with backticks.
std::string wrapIdentifiersWithBackticks(const ASTPtr & root)
{
if (auto identifier = std::dynamic_pointer_cast<ASTIdentifier>(root))
return backQuote(identifier->name);
if (auto function = std::dynamic_pointer_cast<ASTFunction>(root))
return function->name + '(' + wrapIdentifiersWithBackticks(function->arguments) + ')';
if (auto expression_list = std::dynamic_pointer_cast<ASTExpressionList>(root))
{
Names function_arguments(expression_list->children.size());
for (size_t i = 0; i < expression_list->children.size(); ++i)
function_arguments[i] = wrapIdentifiersWithBackticks(expression_list->children[0]);
return boost::algorithm::join(function_arguments, ", ");
}
throw Exception("Primary key could be represented only as columns or functions from columns.", ErrorCodes::BAD_ARGUMENTS);
}
Names extractPrimaryKeyColumnNames(const ASTPtr & storage_ast)
{
const auto sorting_key_ast = extractOrderBy(storage_ast);
const auto primary_key_ast = extractPrimaryKey(storage_ast);
const auto sorting_key_expr_list = extractKeyExpressionList(sorting_key_ast);
const auto primary_key_expr_list = primary_key_ast
? extractKeyExpressionList(primary_key_ast) : sorting_key_expr_list->clone();
/// Maybe we have to handle VersionedCollapsing engine separately. But in our case in looks pointless.
size_t primary_key_size = primary_key_expr_list->children.size();
size_t sorting_key_size = sorting_key_expr_list->children.size();
if (primary_key_size > sorting_key_size)
throw Exception("Primary key must be a prefix of the sorting key, but its length: "
+ toString(primary_key_size) + " is greater than the sorting key length: " + toString(sorting_key_size),
ErrorCodes::BAD_ARGUMENTS);
Names primary_key_columns;
NameSet primary_key_columns_set;
for (size_t i = 0; i < sorting_key_size; ++i)
{
/// Column name could be represented as a f_1(f_2(...f_n(column_name))).
/// Each f_i could take one or more parameters.
/// We will wrap identifiers with backticks to allow non-standart identifier names.
String sorting_key_column = sorting_key_expr_list->children[i]->getColumnName();
if (i < primary_key_size)
{
String pk_column = primary_key_expr_list->children[i]->getColumnName();
if (pk_column != sorting_key_column)
throw Exception("Primary key must be a prefix of the sorting key, but in position "
+ toString(i) + " its column is " + pk_column + ", not " + sorting_key_column,
ErrorCodes::BAD_ARGUMENTS);
if (!primary_key_columns_set.emplace(pk_column).second)
throw Exception("Primary key contains duplicate columns", ErrorCodes::BAD_ARGUMENTS);
primary_key_columns.push_back(wrapIdentifiersWithBackticks(primary_key_expr_list->children[i]));
}
}
return primary_key_columns;
}
bool isReplicatedTableEngine(const ASTPtr & storage_ast)
{
const auto & storage = storage_ast->as<ASTStorage &>();
const auto & engine = storage.engine->as<ASTFunction &>();
if (!endsWith(engine.name, "MergeTree"))
{
String storage_str = queryToString(storage_ast);
throw Exception(
"Unsupported engine was specified in " + storage_str + ", only *MergeTree engines are supported",
ErrorCodes::BAD_ARGUMENTS);
}
return startsWith(engine.name, "Replicated");
}
ShardPriority getReplicasPriority(const Cluster::Addresses & replicas, const std::string & local_hostname, UInt8 random)
{
ShardPriority res;
if (replicas.empty())
return res;
res.is_remote = 1;
for (const auto & replica : replicas)
{
if (isLocalAddress(DNSResolver::instance().resolveHost(replica.host_name)))
{
res.is_remote = 0;
break;
}
}
res.hostname_difference = std::numeric_limits<size_t>::max();
for (const auto & replica : replicas)
{
size_t difference = getHostNameDifference(local_hostname, replica.host_name);
res.hostname_difference = std::min(difference, res.hostname_difference);
}
res.random = random;
return res;
}
}