mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-14 02:12:21 +00:00
330212e0f4
The original motivation for this commit was that shared_ptr_helper used std::shared_ptr<>() which does two heap allocations instead of make_shared<>() which does a single allocation. Turned out that 1. the affected code (--> Storages/) is not on a hot path (rendering the performance argument moot ...) 2. yet copying Storage objects is potentially dangerous and was previously allowed. Hence, this change - removes shared_ptr_helper and as a result all inherited create() methods, - instead, Storage objects are now created using make_shared<>() by the caller (for that to work, many constructors had to be made public), and - all Storage classes were marked as noncopyable using boost::noncopyable. In sum, we are (likely) not making things faster but the code becomes cleaner and harder to misuse.
78 lines
2.5 KiB
C++
78 lines
2.5 KiB
C++
#include <Storages/StorageNull.h>
|
|
#include <Storages/StorageFactory.h>
|
|
#include <Storages/AlterCommands.h>
|
|
|
|
#include <Interpreters/InterpreterAlterQuery.h>
|
|
#include <Interpreters/Context.h>
|
|
#include <Databases/IDatabase.h>
|
|
|
|
#include <IO/WriteHelpers.h>
|
|
|
|
|
|
namespace DB
|
|
{
|
|
|
|
namespace ErrorCodes
|
|
{
|
|
extern const int NOT_IMPLEMENTED;
|
|
extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
|
|
extern const int ALTER_OF_COLUMN_IS_FORBIDDEN;
|
|
}
|
|
|
|
|
|
void registerStorageNull(StorageFactory & factory)
|
|
{
|
|
factory.registerStorage("Null", [](const StorageFactory::Arguments & args)
|
|
{
|
|
if (!args.engine_args.empty())
|
|
throw Exception(
|
|
"Engine " + args.engine_name + " doesn't support any arguments (" + toString(args.engine_args.size()) + " given)",
|
|
ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
|
|
|
|
return std::make_shared<StorageNull>(args.table_id, args.columns, args.constraints, args.comment);
|
|
},
|
|
{
|
|
.supports_parallel_insert = true,
|
|
});
|
|
}
|
|
|
|
void StorageNull::checkAlterIsPossible(const AlterCommands & commands, ContextPtr context) const
|
|
{
|
|
auto name_deps = getDependentViewsByColumn(context);
|
|
for (const auto & command : commands)
|
|
{
|
|
if (command.type != AlterCommand::Type::ADD_COLUMN
|
|
&& command.type != AlterCommand::Type::MODIFY_COLUMN
|
|
&& command.type != AlterCommand::Type::DROP_COLUMN
|
|
&& command.type != AlterCommand::Type::COMMENT_COLUMN
|
|
&& command.type != AlterCommand::Type::COMMENT_TABLE)
|
|
throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Alter of type '{}' is not supported by storage {}",
|
|
command.type, getName());
|
|
|
|
if (command.type == AlterCommand::DROP_COLUMN && !command.clear)
|
|
{
|
|
const auto & deps_mv = name_deps[command.column_name];
|
|
if (!deps_mv.empty())
|
|
{
|
|
throw Exception(
|
|
"Trying to ALTER DROP column " + backQuoteIfNeed(command.column_name) + " which is referenced by materialized view "
|
|
+ toString(deps_mv),
|
|
ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void StorageNull::alter(const AlterCommands & params, ContextPtr context, AlterLockHolder &)
|
|
{
|
|
auto table_id = getStorageID();
|
|
|
|
StorageInMemoryMetadata new_metadata = getInMemoryMetadata();
|
|
params.apply(new_metadata, context);
|
|
DatabaseCatalog::instance().getDatabase(table_id.database_name)->alterTable(context, table_id, new_metadata);
|
|
setInMemoryMetadata(new_metadata);
|
|
}
|
|
|
|
}
|