ClickHouse/dbms/src/Storages/MutationCommands.cpp

84 lines
2.6 KiB
C++

#include <Storages/MutationCommands.h>
#include <IO/Operators.h>
#include <Parsers/formatAST.h>
#include <Parsers/ExpressionListParsers.h>
#include <Parsers/ParserAlterQuery.h>
#include <Parsers/parseQuery.h>
#include <Parsers/ASTAssignment.h>
#include <Common/typeid_cast.h>
namespace DB
{
namespace ErrorCodes
{
extern const int UNKNOWN_MUTATION_COMMAND;
extern const int MULTIPLE_ASSIGNMENTS_TO_COLUMN;
}
std::optional<MutationCommand> MutationCommand::parse(ASTAlterCommand * command)
{
if (command->type == ASTAlterCommand::DELETE)
{
MutationCommand res;
res.ast = command->ptr();
res.type = DELETE;
res.predicate = command->predicate;
return res;
}
else if (command->type == ASTAlterCommand::UPDATE)
{
MutationCommand res;
res.ast = command->ptr();
res.type = UPDATE;
res.predicate = command->predicate;
for (const ASTPtr & assignment_ast : command->update_assignments->children)
{
const auto & assignment = typeid_cast<const ASTAssignment &>(*assignment_ast);
auto insertion = res.column_to_update_expression.emplace(assignment.column_name, assignment.expression);
if (!insertion.second)
throw Exception("Multiple assignments in the single statement to column `" + assignment.column_name + "`",
ErrorCodes::MULTIPLE_ASSIGNMENTS_TO_COLUMN);
}
return res;
}
else
return {};
}
std::shared_ptr<ASTAlterCommandList> MutationCommands::ast() const
{
auto res = std::make_shared<ASTAlterCommandList>();
for (const MutationCommand & command : *this)
res->add(command.ast->clone());
return res;
}
void MutationCommands::writeText(WriteBuffer & out) const
{
std::stringstream commands_ss;
formatAST(*ast(), commands_ss, /* hilite = */ false, /* one_line = */ true);
out << escape << commands_ss.str();
}
void MutationCommands::readText(ReadBuffer & in)
{
String commands_str;
in >> escape >> commands_str;
ParserAlterCommandList p_alter_commands;
auto commands_ast = parseQuery(
p_alter_commands, commands_str.data(), commands_str.data() + commands_str.length(), "mutation commands list", 0);
for (ASTAlterCommand * command_ast : typeid_cast<const ASTAlterCommandList &>(*commands_ast).commands)
{
auto command = MutationCommand::parse(command_ast);
if (!command)
throw Exception("Unknown mutation command type: " + DB::toString<int>(command_ast->type), ErrorCodes::UNKNOWN_MUTATION_COMMAND);
push_back(std::move(*command));
}
}
}