ClickHouse/src/Interpreters/InterpreterCreateQuery.cpp
2022-05-06 14:44:00 +00:00

1607 lines
68 KiB
C++

#include <memory>
#include <filesystem>
#include "Common/Exception.h"
#include <Common/StringUtils/StringUtils.h>
#include <Common/escapeForFileName.h>
#include <Common/typeid_cast.h>
#include <Common/Macros.h>
#include <Common/randomSeed.h>
#include <Common/atomicRename.h>
#include <Common/hex.h>
#include <Core/Defines.h>
#include <Core/Settings.h>
#include <Core/SettingsEnums.h>
#include <IO/WriteBufferFromFile.h>
#include <IO/WriteHelpers.h>
#include <IO/ReadHelpers.h>
#include <Parsers/ASTColumnDeclaration.h>
#include <Parsers/ASTCreateQuery.h>
#include <Parsers/ASTIdentifier.h>
#include <Parsers/ASTIndexDeclaration.h>
#include <Parsers/ASTLiteral.h>
#include <Parsers/ASTInsertQuery.h>
#include <Parsers/ParserCreateQuery.h>
#include <Parsers/formatAST.h>
#include <Parsers/parseQuery.h>
#include <Storages/StorageFactory.h>
#include <Storages/StorageInMemoryMetadata.h>
#include <Storages/StorageReplicatedMergeTree.h>
#include <Interpreters/Context.h>
#include <Interpreters/executeDDLQueryOnCluster.h>
#include <Interpreters/executeQuery.h>
#include <Interpreters/Cluster.h>
#include <Interpreters/DDLTask.h>
#include <Interpreters/ExpressionAnalyzer.h>
#include <Interpreters/InterpreterCreateQuery.h>
#include <Interpreters/InterpreterSelectWithUnionQuery.h>
#include <Interpreters/InterpreterInsertQuery.h>
#include <Interpreters/InterpreterRenameQuery.h>
#include <Interpreters/AddDefaultDatabaseVisitor.h>
#include <Access/Common/AccessRightsElement.h>
#include <DataTypes/DataTypeFactory.h>
#include <DataTypes/NestedUtils.h>
#include <DataTypes/DataTypesNumber.h>
#include <DataTypes/DataTypeLowCardinality.h>
#include <DataTypes/DataTypeNullable.h>
#include <DataTypes/DataTypeAggregateFunction.h>
#include <DataTypes/ObjectUtils.h>
#include <DataTypes/hasNullable.h>
#include <Databases/DatabaseFactory.h>
#include <Databases/DatabaseReplicated.h>
#include <Databases/IDatabase.h>
#include <Databases/DatabaseOnDisk.h>
#include <Databases/TablesLoader.h>
#include <Databases/DDLDependencyVisitor.h>
#include <Compression/CompressionFactory.h>
#include <Interpreters/InterpreterDropQuery.h>
#include <Interpreters/QueryLog.h>
#include <Interpreters/addTypeConversionToAST.h>
#include <Interpreters/FunctionNameNormalizer.h>
#include <Interpreters/ApplyWithSubqueryVisitor.h>
#include <TableFunctions/TableFunctionFactory.h>
#include <Common/logger_useful.h>
namespace DB
{
namespace ErrorCodes
{
extern const int TABLE_ALREADY_EXISTS;
extern const int DICTIONARY_ALREADY_EXISTS;
extern const int EMPTY_LIST_OF_COLUMNS_PASSED;
extern const int INCORRECT_QUERY;
extern const int UNKNOWN_DATABASE_ENGINE;
extern const int DUPLICATE_COLUMN;
extern const int DATABASE_ALREADY_EXISTS;
extern const int BAD_ARGUMENTS;
extern const int BAD_DATABASE_FOR_TEMPORARY_TABLE;
extern const int SUSPICIOUS_TYPE_FOR_LOW_CARDINALITY;
extern const int ILLEGAL_SYNTAX_FOR_DATA_TYPE;
extern const int ILLEGAL_COLUMN;
extern const int LOGICAL_ERROR;
extern const int UNKNOWN_DATABASE;
extern const int PATH_ACCESS_DENIED;
extern const int NOT_IMPLEMENTED;
extern const int ENGINE_REQUIRED;
extern const int UNKNOWN_STORAGE;
}
namespace fs = std::filesystem;
InterpreterCreateQuery::InterpreterCreateQuery(const ASTPtr & query_ptr_, ContextMutablePtr context_)
: WithMutableContext(context_), query_ptr(query_ptr_)
{
}
BlockIO InterpreterCreateQuery::createDatabase(ASTCreateQuery & create)
{
String database_name = create.getDatabase();
auto guard = DatabaseCatalog::instance().getDDLGuard(database_name, "");
/// Database can be created before or it can be created concurrently in another thread, while we were waiting in DDLGuard
if (DatabaseCatalog::instance().isDatabaseExist(database_name))
{
if (create.if_not_exists)
return {};
else
throw Exception("Database " + database_name + " already exists.", ErrorCodes::DATABASE_ALREADY_EXISTS);
}
/// Will write file with database metadata, if needed.
String database_name_escaped = escapeForFileName(database_name);
fs::path metadata_path = fs::canonical(getContext()->getPath());
fs::path metadata_file_tmp_path = metadata_path / "metadata" / (database_name_escaped + ".sql.tmp");
fs::path metadata_file_path = metadata_path / "metadata" / (database_name_escaped + ".sql");
if (!create.storage && create.attach)
{
if (!fs::exists(metadata_file_path))
throw Exception("Database engine must be specified for ATTACH DATABASE query", ErrorCodes::UNKNOWN_DATABASE_ENGINE);
/// Short syntax: try read database definition from file
auto ast = DatabaseOnDisk::parseQueryFromMetadata(nullptr, getContext(), metadata_file_path);
create = ast->as<ASTCreateQuery &>();
if (create.table || !create.storage)
throw Exception(ErrorCodes::INCORRECT_QUERY, "Metadata file {} contains incorrect CREATE DATABASE query", metadata_file_path.string());
create.attach = true;
create.attach_short_syntax = true;
create.setDatabase(database_name);
}
else if (!create.storage)
{
/// For new-style databases engine is explicitly specified in .sql
/// When attaching old-style database during server startup, we must always use Ordinary engine
if (create.attach)
throw Exception("Database engine must be specified for ATTACH DATABASE query", ErrorCodes::UNKNOWN_DATABASE_ENGINE);
bool old_style_database = getContext()->getSettingsRef().default_database_engine.value == DefaultDatabaseEngine::Ordinary;
auto engine = std::make_shared<ASTFunction>();
auto storage = std::make_shared<ASTStorage>();
engine->name = old_style_database ? "Ordinary" : "Atomic";
engine->no_empty_args = true;
storage->set(storage->engine, engine);
create.set(create.storage, storage);
}
else if ((create.columns_list
&& ((create.columns_list->indices && !create.columns_list->indices->children.empty())
|| (create.columns_list->projections && !create.columns_list->projections->children.empty()))))
{
/// Currently, there are no database engines, that support any arguments.
throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE, "Unknown database engine: {}", serializeAST(*create.storage));
}
if (create.storage && !create.storage->engine)
throw Exception(ErrorCodes::INCORRECT_QUERY, "Database engine must be specified");
if (create.storage->engine->name == "Atomic"
|| create.storage->engine->name == "Replicated"
|| create.storage->engine->name == "MaterializedPostgreSQL")
{
if (create.attach && create.uuid == UUIDHelpers::Nil)
throw Exception(ErrorCodes::INCORRECT_QUERY, "UUID must be specified for ATTACH. "
"If you want to attach existing database, use just ATTACH DATABASE {};", create.getDatabase());
else if (create.uuid == UUIDHelpers::Nil)
create.uuid = UUIDHelpers::generateV4();
metadata_path = metadata_path / "store" / DatabaseCatalog::getPathForUUID(create.uuid);
if (!create.attach && fs::exists(metadata_path))
throw Exception(ErrorCodes::DATABASE_ALREADY_EXISTS, "Metadata directory {} already exists", metadata_path.string());
}
else if (create.storage->engine->name == "MaterializeMySQL"
|| create.storage->engine->name == "MaterializedMySQL")
{
/// It creates nested database with Ordinary or Atomic engine depending on UUID in query and default engine setting.
/// Do nothing if it's an internal ATTACH on server startup or short-syntax ATTACH query from user,
/// because we got correct query from the metadata file in this case.
/// If we got query from user, then normalize it first.
bool attach_from_user = create.attach && !internal && !create.attach_short_syntax;
bool create_from_user = !create.attach;
if (create_from_user)
{
const auto & default_engine = getContext()->getSettingsRef().default_database_engine.value;
if (create.uuid == UUIDHelpers::Nil && default_engine == DefaultDatabaseEngine::Atomic)
create.uuid = UUIDHelpers::generateV4(); /// Will enable Atomic engine for nested database
}
else if (attach_from_user && create.uuid == UUIDHelpers::Nil)
{
/// Ambiguity is possible: should we attach nested database as Ordinary
/// or throw "UUID must be specified" for Atomic? So we suggest short syntax for Ordinary.
throw Exception("Use short attach syntax ('ATTACH DATABASE name;' without engine) to attach existing database "
"or specify UUID to attach new database with Atomic engine", ErrorCodes::INCORRECT_QUERY);
}
/// Set metadata path according to nested engine
if (create.uuid == UUIDHelpers::Nil)
metadata_path = metadata_path / "metadata" / database_name_escaped;
else
metadata_path = metadata_path / "store" / DatabaseCatalog::getPathForUUID(create.uuid);
}
else
{
bool is_on_cluster = getContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY;
if (create.uuid != UUIDHelpers::Nil && !is_on_cluster)
throw Exception("Ordinary database engine does not support UUID", ErrorCodes::INCORRECT_QUERY);
/// Ignore UUID if it's ON CLUSTER query
create.uuid = UUIDHelpers::Nil;
metadata_path = metadata_path / "metadata" / database_name_escaped;
}
if ((create.storage->engine->name == "MaterializeMySQL" || create.storage->engine->name == "MaterializedMySQL")
&& !getContext()->getSettingsRef().allow_experimental_database_materialized_mysql
&& !internal)
{
throw Exception("MaterializedMySQL is an experimental database engine. "
"Enable allow_experimental_database_materialized_mysql to use it.", ErrorCodes::UNKNOWN_DATABASE_ENGINE);
}
if (create.storage->engine->name == "Replicated"
&& !getContext()->getSettingsRef().allow_experimental_database_replicated
&& !internal)
{
throw Exception("Replicated is an experimental database engine. "
"Enable allow_experimental_database_replicated to use it.", ErrorCodes::UNKNOWN_DATABASE_ENGINE);
}
if (create.storage->engine->name == "MaterializedPostgreSQL"
&& !getContext()->getSettingsRef().allow_experimental_database_materialized_postgresql
&& !internal)
{
throw Exception("MaterializedPostgreSQL is an experimental database engine. "
"Enable allow_experimental_database_materialized_postgresql to use it.", ErrorCodes::UNKNOWN_DATABASE_ENGINE);
}
DatabasePtr database = DatabaseFactory::get(create, metadata_path / "", getContext());
if (create.uuid != UUIDHelpers::Nil)
create.setDatabase(TABLE_WITH_UUID_NAME_PLACEHOLDER);
bool need_write_metadata = !create.attach || !fs::exists(metadata_file_path);
if (need_write_metadata)
{
create.attach = true;
create.if_not_exists = false;
WriteBufferFromOwnString statement_buf;
formatAST(create, statement_buf, false);
writeChar('\n', statement_buf);
String statement = statement_buf.str();
/// Exclusive flag guarantees, that database is not created right now in another thread.
WriteBufferFromFile out(metadata_file_tmp_path, statement.size(), O_WRONLY | O_CREAT | O_EXCL);
writeString(statement, out);
out.next();
if (getContext()->getSettingsRef().fsync_metadata)
out.sync();
out.close();
}
/// We attach database before loading it's tables, so do not allow concurrent DDL queries
auto db_guard = DatabaseCatalog::instance().getExclusiveDDLGuardForDatabase(database_name);
bool added = false;
bool renamed = false;
try
{
/// TODO Attach db only after it was loaded. Now it's not possible because of view dependencies
DatabaseCatalog::instance().attachDatabase(database_name, database);
added = true;
if (need_write_metadata)
{
/// Prevents from overwriting metadata of detached database
renameNoReplace(metadata_file_tmp_path, metadata_file_path);
renamed = true;
}
if (!load_database_without_tables)
{
/// We use global context here, because storages lifetime is bigger than query context lifetime
TablesLoader loader{getContext()->getGlobalContext(), {{database_name, database}}, has_force_restore_data_flag, create.attach && force_attach}; //-V560
loader.loadTables();
loader.startupTables();
}
}
catch (...)
{
if (renamed)
{
[[maybe_unused]] bool removed = fs::remove(metadata_file_path);
assert(removed);
}
if (added)
DatabaseCatalog::instance().detachDatabase(getContext(), database_name, false, false);
throw;
}
return {};
}
ASTPtr InterpreterCreateQuery::formatColumns(const NamesAndTypesList & columns)
{
auto columns_list = std::make_shared<ASTExpressionList>();
for (const auto & column : columns)
{
const auto column_declaration = std::make_shared<ASTColumnDeclaration>();
column_declaration->name = column.name;
ParserDataType type_parser;
String type_name = column.type->getName();
const char * pos = type_name.data();
const char * end = pos + type_name.size();
column_declaration->type = parseQuery(type_parser, pos, end, "data type", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH);
columns_list->children.emplace_back(column_declaration);
}
return columns_list;
}
ASTPtr InterpreterCreateQuery::formatColumns(const NamesAndTypesList & columns, const NamesAndAliases & alias_columns)
{
std::shared_ptr<ASTExpressionList> columns_list = std::static_pointer_cast<ASTExpressionList>(formatColumns(columns));
for (const auto & alias_column : alias_columns)
{
const auto column_declaration = std::make_shared<ASTColumnDeclaration>();
column_declaration->name = alias_column.name;
ParserDataType type_parser;
String type_name = alias_column.type->getName();
const char * type_pos = type_name.data();
const char * type_end = type_pos + type_name.size();
column_declaration->type = parseQuery(type_parser, type_pos, type_end, "data type", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH);
column_declaration->default_specifier = "ALIAS";
const auto & alias = alias_column.expression;
const char * alias_pos = alias.data();
const char * alias_end = alias_pos + alias.size();
ParserExpression expression_parser;
column_declaration->default_expression = parseQuery(expression_parser, alias_pos, alias_end, "expression", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH);
columns_list->children.emplace_back(column_declaration);
}
return columns_list;
}
ASTPtr InterpreterCreateQuery::formatColumns(const ColumnsDescription & columns)
{
auto columns_list = std::make_shared<ASTExpressionList>();
for (const auto & column : columns)
{
const auto column_declaration = std::make_shared<ASTColumnDeclaration>();
ASTPtr column_declaration_ptr{column_declaration};
column_declaration->name = column.name;
ParserDataType type_parser;
String type_name = column.type->getName();
const char * type_name_pos = type_name.data();
const char * type_name_end = type_name_pos + type_name.size();
column_declaration->type = parseQuery(type_parser, type_name_pos, type_name_end, "data type", 0, DBMS_DEFAULT_MAX_PARSER_DEPTH);
if (column.default_desc.expression)
{
column_declaration->default_specifier = toString(column.default_desc.kind);
column_declaration->default_expression = column.default_desc.expression->clone();
column_declaration->children.push_back(column_declaration->default_expression);
}
if (!column.comment.empty())
{
column_declaration->comment = std::make_shared<ASTLiteral>(Field(column.comment));
column_declaration->children.push_back(column_declaration->comment);
}
if (column.codec)
{
column_declaration->codec = column.codec;
column_declaration->children.push_back(column_declaration->codec);
}
if (column.ttl)
{
column_declaration->ttl = column.ttl;
column_declaration->children.push_back(column_declaration->ttl);
}
columns_list->children.push_back(column_declaration_ptr);
}
return columns_list;
}
ASTPtr InterpreterCreateQuery::formatIndices(const IndicesDescription & indices)
{
auto res = std::make_shared<ASTExpressionList>();
for (const auto & index : indices)
res->children.push_back(index.definition_ast->clone());
return res;
}
ASTPtr InterpreterCreateQuery::formatConstraints(const ConstraintsDescription & constraints)
{
auto res = std::make_shared<ASTExpressionList>();
for (const auto & constraint : constraints.getConstraints())
res->children.push_back(constraint->clone());
return res;
}
ASTPtr InterpreterCreateQuery::formatProjections(const ProjectionsDescription & projections)
{
auto res = std::make_shared<ASTExpressionList>();
for (const auto & projection : projections)
res->children.push_back(projection.definition_ast->clone());
return res;
}
ColumnsDescription InterpreterCreateQuery::getColumnsDescription(
const ASTExpressionList & columns_ast, ContextPtr context_, bool attach)
{
/// First, deduce implicit types.
/** all default_expressions as a single expression list,
* mixed with conversion-columns for each explicitly specified type */
ASTPtr default_expr_list = std::make_shared<ASTExpressionList>();
NamesAndTypesList column_names_and_types;
bool make_columns_nullable = !attach && context_->getSettingsRef().data_type_default_nullable;
for (const auto & ast : columns_ast.children)
{
const auto & col_decl = ast->as<ASTColumnDeclaration &>();
DataTypePtr column_type = nullptr;
if (col_decl.type)
{
column_type = DataTypeFactory::instance().get(col_decl.type);
const auto * aggregate_function_type = typeid_cast<const DataTypeAggregateFunction *>(column_type.get());
if (attach && aggregate_function_type && aggregate_function_type->isVersioned())
aggregate_function_type->setVersion(0, /* if_empty */true);
if (col_decl.null_modifier)
{
if (column_type->isNullable())
throw Exception("Can't use [NOT] NULL modifier with Nullable type", ErrorCodes::ILLEGAL_SYNTAX_FOR_DATA_TYPE);
if (*col_decl.null_modifier)
column_type = makeNullable(column_type);
}
else if (make_columns_nullable)
{
column_type = makeNullable(column_type);
}
else if (!hasNullable(column_type) &&
col_decl.default_specifier == "DEFAULT" &&
col_decl.default_expression &&
col_decl.default_expression->as<ASTLiteral>() &&
col_decl.default_expression->as<ASTLiteral>()->value.isNull())
{
if (column_type->lowCardinality())
{
const auto * low_cardinality_type = typeid_cast<const DataTypeLowCardinality *>(column_type.get());
assert(low_cardinality_type);
column_type = std::make_shared<DataTypeLowCardinality>(makeNullable(low_cardinality_type->getDictionaryType()));
}
else
column_type = makeNullable(column_type);
}
column_names_and_types.emplace_back(col_decl.name, column_type);
}
else
{
/// we're creating dummy DataTypeUInt8 in order to prevent the NullPointerException in ExpressionActions
column_names_and_types.emplace_back(col_decl.name, std::make_shared<DataTypeUInt8>());
}
/// add column to postprocessing if there is a default_expression specified
if (col_decl.default_expression)
{
/** For columns with explicitly-specified type create two expressions:
* 1. default_expression aliased as column name with _tmp suffix
* 2. conversion of expression (1) to explicitly-specified type alias as column name
*/
if (col_decl.type)
{
const auto & final_column_name = col_decl.name;
const auto tmp_column_name = final_column_name + "_tmp_alter" + toString(randomSeed());
const auto * data_type_ptr = column_names_and_types.back().type.get();
default_expr_list->children.emplace_back(
setAlias(addTypeConversionToAST(std::make_shared<ASTIdentifier>(tmp_column_name), data_type_ptr->getName()),
final_column_name));
default_expr_list->children.emplace_back(
setAlias(
col_decl.default_specifier == "EPHEMERAL" ? /// can be ASTLiteral::value NULL
std::make_shared<ASTLiteral>(data_type_ptr->getDefault()) :
col_decl.default_expression->clone(),
tmp_column_name));
}
else
default_expr_list->children.emplace_back(setAlias(col_decl.default_expression->clone(), col_decl.name));
}
}
Block defaults_sample_block;
/// set missing types and wrap default_expression's in a conversion-function if necessary
if (!default_expr_list->children.empty())
defaults_sample_block = validateColumnsDefaultsAndGetSampleBlock(default_expr_list, column_names_and_types, context_);
bool sanity_check_compression_codecs = !attach && !context_->getSettingsRef().allow_suspicious_codecs;
bool allow_experimental_codecs = attach || context_->getSettingsRef().allow_experimental_codecs;
ColumnsDescription res;
auto name_type_it = column_names_and_types.begin();
for (auto ast_it = columns_ast.children.begin(); ast_it != columns_ast.children.end(); ++ast_it, ++name_type_it)
{
ColumnDescription column;
auto & col_decl = (*ast_it)->as<ASTColumnDeclaration &>();
column.name = col_decl.name;
if (col_decl.default_expression)
{
ASTPtr default_expr =
col_decl.default_specifier == "EPHEMERAL" && col_decl.default_expression->as<ASTLiteral>()->value.isNull() ?
std::make_shared<ASTLiteral>(DataTypeFactory::instance().get(col_decl.type)->getDefault()) :
col_decl.default_expression->clone();
if (col_decl.type)
column.type = name_type_it->type;
else
column.type = defaults_sample_block.getByName(column.name).type;
column.default_desc.kind = columnDefaultKindFromString(col_decl.default_specifier);
column.default_desc.expression = default_expr;
}
else if (col_decl.type)
column.type = name_type_it->type;
else
throw Exception();
if (col_decl.comment)
column.comment = col_decl.comment->as<ASTLiteral &>().value.get<String>();
if (col_decl.codec)
{
if (col_decl.default_specifier == "ALIAS")
throw Exception{"Cannot specify codec for column type ALIAS", ErrorCodes::BAD_ARGUMENTS};
column.codec = CompressionCodecFactory::instance().validateCodecAndGetPreprocessedAST(
col_decl.codec, column.type, sanity_check_compression_codecs, allow_experimental_codecs);
}
if (col_decl.ttl)
column.ttl = col_decl.ttl;
res.add(std::move(column));
}
if (!attach && context_->getSettingsRef().flatten_nested)
res.flattenNested();
if (res.getAllPhysical().empty())
throw Exception{"Cannot CREATE table without physical columns", ErrorCodes::EMPTY_LIST_OF_COLUMNS_PASSED};
return res;
}
ConstraintsDescription InterpreterCreateQuery::getConstraintsDescription(const ASTExpressionList * constraints)
{
ASTs constraints_data;
if (constraints)
for (const auto & constraint : constraints->children)
constraints_data.push_back(constraint->clone());
return ConstraintsDescription{constraints_data};
}
InterpreterCreateQuery::TableProperties InterpreterCreateQuery::getTablePropertiesAndNormalizeCreateQuery(ASTCreateQuery & create) const
{
/// Set the table engine if it was not specified explicitly.
setEngine(create);
/// We have to check access rights again (in case engine was changed).
if (create.storage)
{
auto source_access_type = StorageFactory::instance().getSourceAccessType(create.storage->engine->name);
if (source_access_type != AccessType::NONE)
getContext()->checkAccess(source_access_type);
}
TableProperties properties;
TableLockHolder as_storage_lock;
if (create.columns_list)
{
if (create.as_table_function && (create.columns_list->indices || create.columns_list->constraints))
throw Exception("Indexes and constraints are not supported for table functions", ErrorCodes::INCORRECT_QUERY);
if (create.columns_list->columns)
{
properties.columns = getColumnsDescription(*create.columns_list->columns, getContext(), create.attach);
}
if (create.columns_list->indices)
for (const auto & index : create.columns_list->indices->children)
properties.indices.push_back(
IndexDescription::getIndexFromAST(index->clone(), properties.columns, getContext()));
if (create.columns_list->projections)
for (const auto & projection_ast : create.columns_list->projections->children)
{
auto projection = ProjectionDescription::getProjectionFromAST(projection_ast, properties.columns, getContext());
properties.projections.add(std::move(projection));
}
properties.constraints = getConstraintsDescription(create.columns_list->constraints);
}
else if (!create.as_table.empty())
{
String as_database_name = getContext()->resolveDatabase(create.as_database);
StoragePtr as_storage = DatabaseCatalog::instance().getTable({as_database_name, create.as_table}, getContext());
/// as_storage->getColumns() and setEngine(...) must be called under structure lock of other_table for CREATE ... AS other_table.
as_storage_lock = as_storage->lockForShare(getContext()->getCurrentQueryId(), getContext()->getSettingsRef().lock_acquire_timeout);
auto as_storage_metadata = as_storage->getInMemoryMetadataPtr();
properties.columns = as_storage_metadata->getColumns();
/// Secondary indices and projections make sense only for MergeTree family of storage engines.
/// We should not copy them for other storages.
if (create.storage && endsWith(create.storage->engine->name, "MergeTree"))
{
properties.indices = as_storage_metadata->getSecondaryIndices();
properties.projections = as_storage_metadata->getProjections().clone();
}
else
{
/// Only MergeTree support TTL
properties.columns.resetColumnTTLs();
}
properties.constraints = as_storage_metadata->getConstraints();
}
else if (create.select)
{
Block as_select_sample = InterpreterSelectWithUnionQuery::getSampleBlock(create.select->clone(), getContext());
properties.columns = ColumnsDescription(as_select_sample.getNamesAndTypesList());
}
else if (create.as_table_function)
{
/// Table function without columns list.
auto table_function = TableFunctionFactory::instance().get(create.as_table_function, getContext());
properties.columns = table_function->getActualTableStructure(getContext());
}
else if (create.is_dictionary)
{
return {};
}
/// We can have queries like "CREATE TABLE <table> ENGINE=<engine>" if <engine>
/// supports schema inference (will determine table structure in it's constructor).
else if (!StorageFactory::instance().checkIfStorageSupportsSchemaInterface(create.storage->engine->name)) // NOLINT
throw Exception("Incorrect CREATE query: required list of column descriptions or AS section or SELECT.", ErrorCodes::INCORRECT_QUERY);
/// Even if query has list of columns, canonicalize it (unfold Nested columns).
if (!create.columns_list)
create.set(create.columns_list, std::make_shared<ASTColumns>());
ASTPtr new_columns = formatColumns(properties.columns);
ASTPtr new_indices = formatIndices(properties.indices);
ASTPtr new_constraints = formatConstraints(properties.constraints);
ASTPtr new_projections = formatProjections(properties.projections);
create.columns_list->setOrReplace(create.columns_list->columns, new_columns);
create.columns_list->setOrReplace(create.columns_list->indices, new_indices);
create.columns_list->setOrReplace(create.columns_list->constraints, new_constraints);
create.columns_list->setOrReplace(create.columns_list->projections, new_projections);
validateTableStructure(create, properties);
assert(as_database_saved.empty() && as_table_saved.empty());
std::swap(create.as_database, as_database_saved);
std::swap(create.as_table, as_table_saved);
return properties;
}
void InterpreterCreateQuery::validateTableStructure(const ASTCreateQuery & create,
const InterpreterCreateQuery::TableProperties & properties) const
{
/// Check for duplicates
std::set<String> all_columns;
for (const auto & column : properties.columns)
{
if (!all_columns.emplace(column.name).second)
throw Exception("Column " + backQuoteIfNeed(column.name) + " already exists", ErrorCodes::DUPLICATE_COLUMN);
}
const auto & settings = getContext()->getSettingsRef();
/// Check low cardinality types in creating table if it was not allowed in setting
if (!create.attach && !settings.allow_suspicious_low_cardinality_types && !create.is_materialized_view)
{
for (const auto & name_and_type_pair : properties.columns.getAllPhysical())
{
if (const auto * current_type_ptr = typeid_cast<const DataTypeLowCardinality *>(name_and_type_pair.type.get()))
{
if (!isStringOrFixedString(*removeNullable(current_type_ptr->getDictionaryType())))
throw Exception("Creating columns of type " + current_type_ptr->getName() + " is prohibited by default "
"due to expected negative impact on performance. "
"It can be enabled with the \"allow_suspicious_low_cardinality_types\" setting.",
ErrorCodes::SUSPICIOUS_TYPE_FOR_LOW_CARDINALITY);
}
}
}
if (!create.attach && !settings.allow_experimental_geo_types)
{
for (const auto & name_and_type_pair : properties.columns.getAllPhysical())
{
const auto & type = name_and_type_pair.type->getName();
if (type == "MultiPolygon" || type == "Polygon" || type == "Ring" || type == "Point")
{
String message = "Cannot create table with column '" + name_and_type_pair.name + "' which type is '"
+ type + "' because experimental geo types are not allowed. "
+ "Set setting allow_experimental_geo_types = 1 in order to allow it";
throw Exception(message, ErrorCodes::ILLEGAL_COLUMN);
}
}
}
if (!create.attach && !settings.allow_experimental_object_type)
{
for (const auto & [name, type] : properties.columns.getAllPhysical())
{
if (type->hasDynamicSubcolumns())
{
throw Exception(ErrorCodes::ILLEGAL_COLUMN,
"Cannot create table with column '{}' which type is '{}' "
"because experimental Object type is not allowed. "
"Set setting allow_experimental_object_type = 1 in order to allow it",
name, type->getName());
}
}
}
}
String InterpreterCreateQuery::getTableEngineName(DefaultTableEngine default_table_engine)
{
switch (default_table_engine)
{
case DefaultTableEngine::Log:
return "Log";
case DefaultTableEngine::StripeLog:
return "StripeLog";
case DefaultTableEngine::MergeTree:
return "MergeTree";
case DefaultTableEngine::ReplacingMergeTree:
return "ReplacingMergeTree";
case DefaultTableEngine::ReplicatedMergeTree:
return "ReplicatedMergeTree";
case DefaultTableEngine::ReplicatedReplacingMergeTree:
return "ReplicatedReplacingMergeTree";
case DefaultTableEngine::Memory:
return "Memory";
default:
throw Exception("default_table_engine is set to unknown value", ErrorCodes::LOGICAL_ERROR);
}
}
void InterpreterCreateQuery::setDefaultTableEngine(ASTStorage & storage, ContextPtr local_context)
{
if (local_context->getSettingsRef().default_table_engine.value == DefaultTableEngine::None)
throw Exception(ErrorCodes::ENGINE_REQUIRED, "Table engine is not specified in CREATE query");
auto engine_ast = std::make_shared<ASTFunction>();
auto default_table_engine = local_context->getSettingsRef().default_table_engine.value;
engine_ast->name = getTableEngineName(default_table_engine);
engine_ast->no_empty_args = true;
storage.set(storage.engine, engine_ast);
}
void InterpreterCreateQuery::setEngine(ASTCreateQuery & create) const
{
if (create.as_table_function)
return;
if (create.is_dictionary || create.is_ordinary_view || create.is_live_view || create.is_window_view)
return;
if (create.is_materialized_view && create.to_table_id)
return;
if (create.temporary)
{
if (create.storage && create.storage->engine && create.storage->engine->name != "Memory")
throw Exception(ErrorCodes::INCORRECT_QUERY, "Temporary tables can only be created with ENGINE = Memory, not {}",
create.storage->engine->name);
/// It's possible if some part of storage definition (such as PARTITION BY) is specified, but ENGINE is not.
/// It makes sense when default_table_engine setting is used, but not for temporary tables.
/// For temporary tables we ignore this setting to allow CREATE TEMPORARY TABLE query without specifying ENGINE
/// even if setting is set to MergeTree or something like that (otherwise MergeTree will be substituted and query will fail).
if (create.storage && !create.storage->engine)
throw Exception(ErrorCodes::INCORRECT_QUERY, "Invalid storage definition for temporary table: must be either ENGINE = Memory or empty");
auto engine_ast = std::make_shared<ASTFunction>();
engine_ast->name = "Memory";
engine_ast->no_empty_args = true;
auto storage_ast = std::make_shared<ASTStorage>();
storage_ast->set(storage_ast->engine, engine_ast);
create.set(create.storage, storage_ast);
return;
}
if (create.storage)
{
/// Some part of storage definition (such as PARTITION BY) is specified, but ENGINE is not: just set default one.
if (!create.storage->engine)
setDefaultTableEngine(*create.storage, getContext());
return;
}
if (!create.as_table.empty())
{
/// NOTE Getting the structure from the table specified in the AS is done not atomically with the creation of the table.
String as_database_name = getContext()->resolveDatabase(create.as_database);
String as_table_name = create.as_table;
ASTPtr as_create_ptr = DatabaseCatalog::instance().getDatabase(as_database_name)->getCreateTableQuery(as_table_name, getContext());
const auto & as_create = as_create_ptr->as<ASTCreateQuery &>();
const String qualified_name = backQuoteIfNeed(as_database_name) + "." + backQuoteIfNeed(as_table_name);
if (as_create.is_ordinary_view)
throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a View", qualified_name);
if (as_create.is_live_view)
throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a Live View", qualified_name);
if (as_create.is_window_view)
throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a Window View", qualified_name);
if (as_create.is_dictionary)
throw Exception(ErrorCodes::INCORRECT_QUERY, "Cannot CREATE a table AS {}, it is a Dictionary", qualified_name);
if (as_create.storage)
create.set(create.storage, as_create.storage->ptr());
else if (as_create.as_table_function)
create.as_table_function = as_create.as_table_function->clone();
else
throw Exception(ErrorCodes::LOGICAL_ERROR, "Cannot set engine, it's a bug.");
return;
}
create.set(create.storage, std::make_shared<ASTStorage>());
setDefaultTableEngine(*create.storage, getContext());
}
static void generateUUIDForTable(ASTCreateQuery & create)
{
if (create.uuid == UUIDHelpers::Nil)
create.uuid = UUIDHelpers::generateV4();
/// If destination table (to_table_id) is not specified for materialized view,
/// then MV will create inner table. We should generate UUID of inner table here,
/// so it will be the same on all hosts if query in ON CLUSTER or database engine is Replicated.
bool need_uuid_for_inner_table = !create.attach && create.is_materialized_view && !create.to_table_id;
if (need_uuid_for_inner_table && create.to_inner_uuid == UUIDHelpers::Nil)
create.to_inner_uuid = UUIDHelpers::generateV4();
}
void InterpreterCreateQuery::assertOrSetUUID(ASTCreateQuery & create, const DatabasePtr & database) const
{
const auto * kind = create.is_dictionary ? "Dictionary" : "Table";
const auto * kind_upper = create.is_dictionary ? "DICTIONARY" : "TABLE";
if (database->getEngineName() == "Replicated" && getContext()->getClientInfo().is_replicated_database_internal
&& !internal)
{
if (create.uuid == UUIDHelpers::Nil)
throw Exception("Table UUID is not specified in DDL log", ErrorCodes::LOGICAL_ERROR);
}
bool from_path = create.attach_from_path.has_value();
if (database->getUUID() != UUIDHelpers::Nil)
{
if (create.attach && !from_path && create.uuid == UUIDHelpers::Nil)
{
throw Exception(ErrorCodes::INCORRECT_QUERY,
"Incorrect ATTACH {} query for Atomic database engine. "
"Use one of the following queries instead:\n"
"1. ATTACH {} {};\n"
"2. CREATE {} {} <table definition>;\n"
"3. ATTACH {} {} FROM '/path/to/data/' <table definition>;\n"
"4. ATTACH {} {} UUID '<uuid>' <table definition>;",
kind_upper,
kind_upper, create.table,
kind_upper, create.table,
kind_upper, create.table,
kind_upper, create.table);
}
generateUUIDForTable(create);
}
else
{
bool is_on_cluster = getContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY;
bool has_uuid = create.uuid != UUIDHelpers::Nil || create.to_inner_uuid != UUIDHelpers::Nil;
if (has_uuid && !is_on_cluster)
throw Exception(ErrorCodes::INCORRECT_QUERY,
"{} UUID specified, but engine of database {} is not Atomic", kind, create.getDatabase());
/// Ignore UUID if it's ON CLUSTER query
create.uuid = UUIDHelpers::Nil;
create.to_inner_uuid = UUIDHelpers::Nil;
}
}
BlockIO InterpreterCreateQuery::createTable(ASTCreateQuery & create)
{
/// Temporary tables are created out of databases.
if (create.temporary && create.database)
throw Exception("Temporary tables cannot be inside a database. You should not specify a database for a temporary table.",
ErrorCodes::BAD_DATABASE_FOR_TEMPORARY_TABLE);
String current_database = getContext()->getCurrentDatabase();
auto database_name = create.database ? create.getDatabase() : current_database;
// If this is a stub ATTACH query, read the query definition from the database
if (create.attach && !create.storage && !create.columns_list)
{
auto database = DatabaseCatalog::instance().getDatabase(database_name);
if (database->getEngineName() == "Replicated")
{
auto guard = DatabaseCatalog::instance().getDDLGuard(database_name, create.getTable());
if (auto * ptr = typeid_cast<DatabaseReplicated *>(database.get());
ptr && !getContext()->getClientInfo().is_replicated_database_internal)
{
create.setDatabase(database_name);
guard->releaseTableLock();
return ptr->tryEnqueueReplicatedDDL(query_ptr, getContext(), internal);
}
}
bool if_not_exists = create.if_not_exists;
// Table SQL definition is available even if the table is detached (even permanently)
auto query = database->getCreateTableQuery(create.getTable(), getContext());
auto create_query = query->as<ASTCreateQuery &>();
if (!create.is_dictionary && create_query.is_dictionary)
throw Exception(ErrorCodes::INCORRECT_QUERY,
"Cannot ATTACH TABLE {}.{}, it is a Dictionary",
backQuoteIfNeed(database_name), backQuoteIfNeed(create.getTable()));
if (create.is_dictionary && !create_query.is_dictionary)
throw Exception(ErrorCodes::INCORRECT_QUERY,
"Cannot ATTACH DICTIONARY {}.{}, it is a Table",
backQuoteIfNeed(database_name), backQuoteIfNeed(create.getTable()));
create = create_query; // Copy the saved create query, but use ATTACH instead of CREATE
create.attach = true;
create.attach_short_syntax = true;
create.if_not_exists = if_not_exists;
}
/// TODO throw exception if !create.attach_short_syntax && !create.attach_from_path && !internal
if (create.attach_from_path)
{
fs::path user_files = fs::path(getContext()->getUserFilesPath()).lexically_normal();
fs::path root_path = fs::path(getContext()->getPath()).lexically_normal();
if (getContext()->getClientInfo().query_kind == ClientInfo::QueryKind::INITIAL_QUERY)
{
fs::path data_path = fs::path(*create.attach_from_path).lexically_normal();
if (data_path.is_relative())
data_path = (user_files / data_path).lexically_normal();
if (!startsWith(data_path, user_files))
throw Exception(ErrorCodes::PATH_ACCESS_DENIED,
"Data directory {} must be inside {} to attach it", String(data_path), String(user_files));
/// Data path must be relative to root_path
create.attach_from_path = fs::relative(data_path, root_path) / "";
}
else
{
fs::path data_path = (root_path / *create.attach_from_path).lexically_normal();
if (!startsWith(data_path, user_files))
throw Exception(ErrorCodes::PATH_ACCESS_DENIED,
"Data directory {} must be inside {} to attach it", String(data_path), String(user_files));
}
}
else if (create.attach && !create.attach_short_syntax && getContext()->getClientInfo().query_kind != ClientInfo::QueryKind::SECONDARY_QUERY)
{
auto * log = &Poco::Logger::get("InterpreterCreateQuery");
LOG_WARNING(log, "ATTACH TABLE query with full table definition is not recommended: "
"use either ATTACH TABLE {}; to attach existing table "
"or CREATE TABLE {} <table definition>; to create new table "
"or ATTACH TABLE {} FROM '/path/to/data/' <table definition>; to create new table and attach data.",
create.getTable(), create.getTable(), create.getTable());
}
if (!create.temporary && !create.database)
create.setDatabase(current_database);
if (create.to_table_id && create.to_table_id.database_name.empty())
create.to_table_id.database_name = current_database;
if (create.select && create.isView())
{
// Expand CTE before filling default database
ApplyWithSubqueryVisitor().visit(*create.select);
AddDefaultDatabaseVisitor visitor(getContext(), current_database);
visitor.visit(*create.select);
}
if (create.columns_list)
{
AddDefaultDatabaseVisitor visitor(getContext(), current_database);
visitor.visit(*create.columns_list);
}
/// Set and retrieve list of columns, indices and constraints. Set table engine if needed. Rewrite query in canonical way.
TableProperties properties = getTablePropertiesAndNormalizeCreateQuery(create);
/// Check type compatible for materialized dest table and select columns
if (create.select && create.is_materialized_view && create.to_table_id)
{
if (StoragePtr to_table = DatabaseCatalog::instance().tryGetTable(
{create.to_table_id.database_name, create.to_table_id.table_name, create.to_table_id.uuid},
getContext()
))
{
Block input_block = InterpreterSelectWithUnionQuery(
create.select->clone(), getContext(), SelectQueryOptions().analyze()).getSampleBlock();
Block output_block = to_table->getInMemoryMetadataPtr()->getSampleBlock();
ColumnsWithTypeAndName input_columns;
ColumnsWithTypeAndName output_columns;
for (const auto & input_column : input_block)
{
if (const auto * output_column = output_block.findByName(input_column.name))
{
input_columns.push_back(input_column.cloneEmpty());
output_columns.push_back(output_column->cloneEmpty());
}
}
ActionsDAG::makeConvertingActions(
input_columns,
output_columns,
ActionsDAG::MatchColumnsMode::Position
);
}
}
DatabasePtr database;
bool need_add_to_database = !create.temporary;
if (need_add_to_database)
database = DatabaseCatalog::instance().getDatabase(database_name);
if (need_add_to_database && database->getEngineName() == "Replicated")
{
auto guard = DatabaseCatalog::instance().getDDLGuard(create.getDatabase(), create.getTable());
if (auto * ptr = typeid_cast<DatabaseReplicated *>(database.get());
ptr && !getContext()->getClientInfo().is_replicated_database_internal)
{
assertOrSetUUID(create, database);
guard->releaseTableLock();
return ptr->tryEnqueueReplicatedDDL(query_ptr, getContext(), internal);
}
}
if (create.replace_table)
return doCreateOrReplaceTable(create, properties);
/// Actually creates table
bool created = doCreateTable(create, properties);
if (!created) /// Table already exists
return {};
/// If table has dependencies - add them to the graph
QualifiedTableName qualified_name{database_name, create.getTable()};
TableNamesSet loading_dependencies = getDependenciesSetFromCreateQuery(getContext()->getGlobalContext(), qualified_name, query_ptr);
if (!loading_dependencies.empty())
DatabaseCatalog::instance().addLoadingDependencies(qualified_name, std::move(loading_dependencies));
return fillTableIfNeeded(create);
}
bool InterpreterCreateQuery::doCreateTable(ASTCreateQuery & create,
const InterpreterCreateQuery::TableProperties & properties)
{
std::unique_ptr<DDLGuard> guard;
String data_path;
DatabasePtr database;
bool need_add_to_database = !create.temporary;
if (need_add_to_database)
{
/** If the request specifies IF NOT EXISTS, we allow concurrent CREATE queries (which do nothing).
* If table doesn't exist, one thread is creating table, while others wait in DDLGuard.
*/
guard = DatabaseCatalog::instance().getDDLGuard(create.getDatabase(), create.getTable());
database = DatabaseCatalog::instance().getDatabase(create.getDatabase());
assertOrSetUUID(create, database);
String storage_name = create.is_dictionary ? "Dictionary" : "Table";
auto storage_already_exists_error_code = create.is_dictionary ? ErrorCodes::DICTIONARY_ALREADY_EXISTS : ErrorCodes::TABLE_ALREADY_EXISTS;
/// Table can be created before or it can be created concurrently in another thread, while we were waiting in DDLGuard.
if (database->isTableExist(create.getTable(), getContext()))
{
/// TODO Check structure of table
if (create.if_not_exists)
return false;
else if (create.replace_view)
{
/// when executing CREATE OR REPLACE VIEW, drop current existing view
auto drop_ast = std::make_shared<ASTDropQuery>();
drop_ast->setDatabase(create.getDatabase());
drop_ast->setTable(create.getTable());
drop_ast->no_ddl_lock = true;
auto drop_context = Context::createCopy(context);
InterpreterDropQuery interpreter(drop_ast, drop_context);
interpreter.execute();
}
else
throw Exception(storage_already_exists_error_code,
"{} {}.{} already exists", storage_name, backQuoteIfNeed(create.getDatabase()), backQuoteIfNeed(create.getTable()));
}
else if (!create.attach)
{
/// Checking that table may exists in detached/detached permanently state
try
{
database->checkMetadataFilenameAvailability(create.getTable());
}
catch (const Exception &)
{
if (create.if_not_exists)
return false;
throw;
}
}
data_path = database->getTableDataPath(create);
if (!create.attach && !data_path.empty() && fs::exists(fs::path{getContext()->getPath()} / data_path))
throw Exception(storage_already_exists_error_code,
"Directory for {} data {} already exists", Poco::toLower(storage_name), String(data_path));
}
else
{
if (create.if_not_exists && getContext()->tryResolveStorageID({"", create.getTable()}, Context::ResolveExternal))
return false;
String temporary_table_name = create.getTable();
auto temporary_table = TemporaryTableHolder(getContext(), properties.columns, properties.constraints, query_ptr);
getContext()->getSessionContext()->addExternalTable(temporary_table_name, std::move(temporary_table));
return true;
}
bool from_path = create.attach_from_path.has_value();
String actual_data_path = data_path;
if (from_path)
{
if (data_path.empty())
throw Exception(ErrorCodes::NOT_IMPLEMENTED,
"ATTACH ... FROM ... query is not supported for {} database engine", database->getEngineName());
/// We will try to create Storage instance with provided data path
data_path = *create.attach_from_path;
create.attach_from_path = std::nullopt;
}
if (create.attach)
{
/// If table was detached it's not possible to attach it back while some threads are using
/// old instance of the storage. For example, AsynchronousMetrics may cause ATTACH to fail,
/// so we allow waiting here. If database_atomic_wait_for_drop_and_detach_synchronously is disabled
/// and old storage instance still exists it will throw exception.
if (getContext()->getSettingsRef().database_atomic_wait_for_drop_and_detach_synchronously)
database->waitDetachedTableNotInUse(create.uuid);
else
database->checkDetachedTableNotInUse(create.uuid);
}
StoragePtr res;
/// NOTE: CREATE query may be rewritten by Storage creator or table function
if (create.as_table_function)
{
const auto & factory = TableFunctionFactory::instance();
auto table_func = factory.get(create.as_table_function, getContext());
/// In case of CREATE AS table_function() query we should use global context
/// in storage creation because there will be no query context on server startup
/// and because storage lifetime is bigger than query context lifetime.
res = table_func->execute(create.as_table_function, getContext(), create.getTable(), properties.columns, /*use_global_context=*/true);
res->renameInMemory({create.getDatabase(), create.getTable(), create.uuid});
}
else
{
res = StorageFactory::instance().get(create,
data_path,
getContext(),
getContext()->getGlobalContext(),
properties.columns,
properties.constraints,
false);
/// If schema wes inferred while storage creation, add columns description to create query.
addColumnsDescriptionToCreateQueryIfNecessary(query_ptr->as<ASTCreateQuery &>(), res);
}
if (!create.attach && getContext()->getSettingsRef().database_replicated_allow_only_replicated_engine)
{
bool is_replicated_storage = typeid_cast<const StorageReplicatedMergeTree *>(res.get()) != nullptr;
if (!is_replicated_storage && res->storesDataOnDisk() && database && database->getEngineName() == "Replicated")
throw Exception(ErrorCodes::UNKNOWN_STORAGE,
"Only tables with a Replicated engine or tables which do not store data on disk are allowed in a Replicated database");
}
if (from_path && !res->storesDataOnDisk())
throw Exception(ErrorCodes::NOT_IMPLEMENTED,
"ATTACH ... FROM ... query is not supported for {} table engine, "
"because such tables do not store any data on disk. Use CREATE instead.", res->getName());
database->createTable(getContext(), create.getTable(), res, query_ptr);
/// Move table data to the proper place. Wo do not move data earlier to avoid situations
/// when data directory moved, but table has not been created due to some error.
if (from_path)
res->rename(actual_data_path, {create.getDatabase(), create.getTable(), create.uuid});
/// We must call "startup" and "shutdown" while holding DDLGuard.
/// Because otherwise method "shutdown" (from InterpreterDropQuery) can be called before startup
/// (in case when table was created and instantly dropped before started up)
///
/// Method "startup" may create background tasks and method "shutdown" will wait for them.
/// But if "shutdown" is called before "startup", it will exit early, because there are no background tasks to wait.
/// Then background task is created by "startup" method. And when destructor of a table object is called, background task is still active,
/// and the task will use references to freed data.
/// Also note that "startup" method is exception-safe. If exception is thrown from "startup",
/// we can safely destroy the object without a call to "shutdown", because there is guarantee
/// that no background threads/similar resources remain after exception from "startup".
if (!res->supportsDynamicSubcolumns() && hasDynamicSubcolumns(res->getInMemoryMetadataPtr()->getColumns()))
{
throw Exception(ErrorCodes::ILLEGAL_COLUMN,
"Cannot create table with column of type Object, "
"because storage {} doesn't support dynamic subcolumns",
res->getName());
}
res->startup();
return true;
}
BlockIO InterpreterCreateQuery::doCreateOrReplaceTable(ASTCreateQuery & create,
const InterpreterCreateQuery::TableProperties & properties)
{
/// Replicated database requires separate contexts for each DDL query
ContextPtr current_context = getContext();
ContextMutablePtr create_context = Context::createCopy(current_context);
create_context->setQueryContext(std::const_pointer_cast<Context>(current_context));
auto make_drop_context = [&](bool on_error) -> ContextMutablePtr
{
ContextMutablePtr drop_context = Context::createCopy(current_context);
drop_context->makeQueryContext();
if (on_error)
return drop_context;
if (auto txn = current_context->getZooKeeperMetadataTransaction())
{
/// Execute drop as separate query, because [CREATE OR] REPLACE query can be considered as
/// successfully executed after RENAME/EXCHANGE query.
drop_context->resetZooKeeperMetadataTransaction();
auto drop_txn = std::make_shared<ZooKeeperMetadataTransaction>(txn->getZooKeeper(), txn->getDatabaseZooKeeperPath(),
txn->isInitialQuery(), txn->getTaskZooKeeperPath());
drop_context->initZooKeeperMetadataTransaction(drop_txn);
}
return drop_context;
};
auto ast_drop = std::make_shared<ASTDropQuery>();
String table_to_replace_name = create.getTable();
{
auto database = DatabaseCatalog::instance().getDatabase(create.getDatabase());
if (database->getUUID() == UUIDHelpers::Nil)
throw Exception(ErrorCodes::INCORRECT_QUERY,
"{} query is supported only for Atomic databases",
create.create_or_replace ? "CREATE OR REPLACE TABLE" : "REPLACE TABLE");
UInt64 name_hash = sipHash64(create.getDatabase() + create.getTable());
UInt16 random_suffix = thread_local_rng();
if (auto txn = current_context->getZooKeeperMetadataTransaction())
{
/// Avoid different table name on database replicas
random_suffix = sipHash64(txn->getTaskZooKeeperPath());
}
create.setTable(fmt::format("_tmp_replace_{}_{}",
getHexUIntLowercase(name_hash),
getHexUIntLowercase(random_suffix)));
ast_drop->setTable(create.getTable());
ast_drop->is_dictionary = create.is_dictionary;
ast_drop->setDatabase(create.getDatabase());
ast_drop->kind = ASTDropQuery::Drop;
}
bool created = false;
bool renamed = false;
try
{
/// Create temporary table (random name will be generated)
[[maybe_unused]] bool done = InterpreterCreateQuery(query_ptr, create_context).doCreateTable(create, properties);
assert(done);
created = true;
/// Try fill temporary table
BlockIO fill_io = fillTableIfNeeded(create);
executeTrivialBlockIO(fill_io, getContext());
/// Replace target table with created one
auto ast_rename = std::make_shared<ASTRenameQuery>();
ASTRenameQuery::Element elem
{
ASTRenameQuery::Table{create.getDatabase(), create.getTable()},
ASTRenameQuery::Table{create.getDatabase(), table_to_replace_name}
};
ast_rename->elements.push_back(std::move(elem));
ast_rename->dictionary = create.is_dictionary;
if (create.create_or_replace)
{
/// CREATE OR REPLACE TABLE
/// Will execute ordinary RENAME instead of EXCHANGE if the target table does not exist
ast_rename->rename_if_cannot_exchange = true;
ast_rename->exchange = false;
}
else
{
/// REPLACE TABLE
/// Will execute EXCHANGE query and fail if the target table does not exist
ast_rename->exchange = true;
}
InterpreterRenameQuery interpreter_rename{ast_rename, current_context};
interpreter_rename.execute();
renamed = true;
if (!interpreter_rename.renamedInsteadOfExchange())
{
/// Target table was replaced with new one, drop old table
auto drop_context = make_drop_context(false);
InterpreterDropQuery(ast_drop, drop_context).execute();
}
create.setTable(table_to_replace_name);
return {};
}
catch (...)
{
/// Drop temporary table if it was successfully created, but was not renamed to target name
if (created && !renamed)
{
auto drop_context = make_drop_context(true);
InterpreterDropQuery(ast_drop, drop_context).execute();
}
throw;
}
}
BlockIO InterpreterCreateQuery::fillTableIfNeeded(const ASTCreateQuery & create)
{
/// If the query is a CREATE SELECT, insert the data into the table.
if (create.select && !create.attach
&& !create.is_ordinary_view && !create.is_live_view && !create.is_window_view
&& (!create.is_materialized_view || create.is_populate))
{
auto insert = std::make_shared<ASTInsertQuery>();
insert->table_id = {create.getDatabase(), create.getTable(), create.uuid};
insert->select = create.select->clone();
return InterpreterInsertQuery(insert, getContext(),
getContext()->getSettingsRef().insert_allow_materialized_columns).execute();
}
return {};
}
void InterpreterCreateQuery::prepareOnClusterQuery(ASTCreateQuery & create, ContextPtr local_context, const String & cluster_name)
{
if (create.attach)
return;
/// For CREATE query generate UUID on initiator, so it will be the same on all hosts.
/// It will be ignored if database does not support UUIDs.
generateUUIDForTable(create);
/// For cross-replication cluster we cannot use UUID in replica path.
String cluster_name_expanded = local_context->getMacros()->expand(cluster_name);
ClusterPtr cluster = local_context->getCluster(cluster_name_expanded);
if (cluster->maybeCrossReplication())
{
/// Check that {uuid} macro is not used in zookeeper_path for ReplicatedMergeTree.
/// Otherwise replicas will generate different paths.
if (!create.storage)
return;
if (!create.storage->engine)
return;
if (!startsWith(create.storage->engine->name, "Replicated"))
return;
bool has_explicit_zk_path_arg = create.storage->engine->arguments &&
create.storage->engine->arguments->children.size() >= 2 &&
create.storage->engine->arguments->children[0]->as<ASTLiteral>() &&
create.storage->engine->arguments->children[0]->as<ASTLiteral>()->value.getType() == Field::Types::String;
if (has_explicit_zk_path_arg)
{
String zk_path = create.storage->engine->arguments->children[0]->as<ASTLiteral>()->value.get<String>();
Macros::MacroExpansionInfo info;
info.table_id.uuid = create.uuid;
info.ignore_unknown = true;
local_context->getMacros()->expand(zk_path, info);
if (!info.expanded_uuid)
return;
}
throw Exception("Seems like cluster is configured for cross-replication, "
"but zookeeper_path for ReplicatedMergeTree is not specified or contains {uuid} macro. "
"It's not supported for cross replication, because tables must have different UUIDs. "
"Please specify unique zookeeper_path explicitly.", ErrorCodes::INCORRECT_QUERY);
}
}
BlockIO InterpreterCreateQuery::execute()
{
FunctionNameNormalizer().visit(query_ptr.get());
auto & create = query_ptr->as<ASTCreateQuery &>();
if (!create.cluster.empty())
{
prepareOnClusterQuery(create, getContext(), create.cluster);
DDLQueryOnClusterParams params;
params.access_to_check = getRequiredAccess();
return executeDDLQueryOnCluster(query_ptr, getContext(), params);
}
getContext()->checkAccess(getRequiredAccess());
ASTQueryWithOutput::resetOutputASTIfExist(create);
/// CREATE|ATTACH DATABASE
if (create.database && !create.table)
return createDatabase(create);
else
return createTable(create);
}
AccessRightsElements InterpreterCreateQuery::getRequiredAccess() const
{
/// Internal queries (initiated by the server itself) always have access to everything.
if (internal)
return {};
AccessRightsElements required_access;
const auto & create = query_ptr->as<const ASTCreateQuery &>();
if (!create.table)
{
required_access.emplace_back(AccessType::CREATE_DATABASE, create.getDatabase());
}
else if (create.is_dictionary)
{
required_access.emplace_back(AccessType::CREATE_DICTIONARY, create.getDatabase(), create.getTable());
}
else if (create.isView())
{
assert(!create.temporary);
if (create.replace_view)
required_access.emplace_back(AccessType::DROP_VIEW | AccessType::CREATE_VIEW, create.getDatabase(), create.getTable());
else
required_access.emplace_back(AccessType::CREATE_VIEW, create.getDatabase(), create.getTable());
}
else
{
if (create.temporary)
required_access.emplace_back(AccessType::CREATE_TEMPORARY_TABLE);
else
{
if (create.replace_table)
required_access.emplace_back(AccessType::DROP_TABLE, create.getDatabase(), create.getTable());
required_access.emplace_back(AccessType::CREATE_TABLE, create.getDatabase(), create.getTable());
}
}
if (create.to_table_id)
required_access.emplace_back(AccessType::SELECT | AccessType::INSERT, create.to_table_id.database_name, create.to_table_id.table_name);
if (create.storage && create.storage->engine)
{
auto source_access_type = StorageFactory::instance().getSourceAccessType(create.storage->engine->name);
if (source_access_type != AccessType::NONE)
required_access.emplace_back(source_access_type);
}
return required_access;
}
void InterpreterCreateQuery::extendQueryLogElemImpl(QueryLogElement & elem, const ASTPtr &, ContextPtr) const
{
elem.query_kind = "Create";
if (!as_table_saved.empty())
{
String database = backQuoteIfNeed(as_database_saved.empty() ? getContext()->getCurrentDatabase() : as_database_saved);
elem.query_databases.insert(database);
elem.query_tables.insert(database + "." + backQuoteIfNeed(as_table_saved));
}
}
void InterpreterCreateQuery::addColumnsDescriptionToCreateQueryIfNecessary(ASTCreateQuery & create, const StoragePtr & storage)
{
if (create.is_dictionary || (create.columns_list && create.columns_list->columns && !create.columns_list->columns->children.empty()))
return;
auto ast_storage = std::make_shared<ASTStorage>();
auto query_from_storage = DB::getCreateQueryFromStorage(storage, ast_storage, false,
getContext()->getSettingsRef().max_parser_depth, true);
auto & create_query_from_storage = query_from_storage->as<ASTCreateQuery &>();
if (!create.columns_list)
{
ASTPtr columns_list = std::make_shared<ASTColumns>(*create_query_from_storage.columns_list);
create.set(create.columns_list, columns_list);
}
else
{
ASTPtr columns = std::make_shared<ASTExpressionList>(*create_query_from_storage.columns_list->columns);
create.columns_list->set(create.columns_list->columns, columns);
}
}
}