ClickHouse/dbms/src/Parsers/ParserSystemQuery.cpp

#include <Parsers/ParserSystemQuery.h>
#include <Parsers/ASTSystemQuery.h>
#include <Parsers/CommonParsers.h>
#include <Parsers/ASTLiteral.h>
#include <Interpreters/evaluateConstantExpression.h>


namespace ErrorCodes
{
    extern const int NOT_IMPLEMENTED;
}


namespace DB
{


bool ParserSystemQuery::parseImpl(IParser::Pos & pos, ASTPtr & node, Expected & expected)
{
    auto begin = pos;

    if (!ParserKeyword{"SYSTEM"}.ignore(pos))
        return false;

    using Type = ASTSystemQuery::Type;

    auto res = std::make_shared<ASTSystemQuery>();

    bool found = false;
    for (int i = static_cast<int>(Type::UNKNOWN) + 1; i < static_cast<int>(Type::END); ++i)
    {
        Type t = static_cast<Type>(i);
        if (ParserKeyword{ASTSystemQuery::typeToString(t)}.ignore(pos))
        {
            res->type = t;
            found = true;
        }
    }

    if (!found)
        return false;

    if (res->type == Type::RELOAD_DICTIONARY)
    {
        if (!parseIdentifierOrStringLiteral(pos, expected, res->target_dictionary))
            return false;
    }
    else if (res->type == Type::SYNC_REPLICA)
    {
        throw Exception("SYNC REPLICA is not supported yet", ErrorCodes::NOT_IMPLEMENTED);
    }

    res->range = {begin, pos};
    node = std::move(res);
    return true;
}

}