ASTPtr DatabaseDictionary::getCreateTableQueryImpl(const Context & context,
const String & table_name, bool throw_on_error) const
{
String query;
{
WriteBufferFromString buffer(query);
const auto & dictionaries = context.getExternalDictionaries();
auto dictionary = throw_on_error ? dictionaries.getDictionary(table_name)
: dictionaries.tryGetDictionary(table_name);
auto names_and_types = StorageDictionary::getNamesAndTypes(dictionary->getStructure());
buffer << "CREATE TABLE " << backQuoteIfNeed(name) << '.' << backQuoteIfNeed(table_name) << " (";
buffer << StorageDictionary::generateNamesAndTypesDescription(names_and_types.begin(), names_and_types.end());
buffer << ") Engine = Dictionary(" << backQuoteIfNeed(table_name) << ")";
}
ParserCreateQuery parser;
const char * pos = query.data();
std::string error_message;
auto ast = tryParseQuery(parser, pos, pos + query.size(), error_message,
/* hilite = */ false, "", /* allow_multi_statements = */ false, 0);
if (!ast && throw_on_error)
throw Exception(error_message, ErrorCodes::SYNTAX_ERROR);
return ast;
}
static ASTPtr getQueryFromMetadata(const String & metadata_path, bool throw_on_error = true)
{
if (!Poco::File(metadata_path).exists())
return nullptr;
String query;
{
ReadBufferFromFile in(metadata_path, 4096);
readStringUntilEOF(query, in);
}
ParserCreateQuery parser;
const char * pos = query.data();
std::string error_message;
auto ast = tryParseQuery(parser, pos, pos + query.size(), error_message, /* hilite = */ false,
"in file " + metadata_path, /* allow_multi_statements = */ false, 0);
if (!ast && throw_on_error)
throw Exception(error_message, ErrorCodes::SYNTAX_ERROR);
return ast;
}
