#include #include #include namespace DB { namespace ErrorCodes { extern const int NOT_FOUND_COLUMN_IN_BLOCK; extern const int EMPTY_LIST_OF_COLUMNS_QUERIED; extern const int NO_SUCH_COLUMN_IN_TABLE; extern const int COLUMN_QUERIED_MORE_THAN_ONCE; } NamesAndTypesList StorageSnapshot::getColumns(const GetColumnsOptions & options) const { auto all_columns = metadata->getColumns().get(options); if (options.with_virtuals) { /// Virtual columns must be appended after ordinary, /// because user can override them. auto virtuals = storage.getVirtuals(); if (!virtuals.empty()) { NameSet column_names; for (const auto & column : all_columns) column_names.insert(column.name); for (auto && column : virtuals) if (!column_names.count(column.name)) all_columns.push_back(std::move(column)); } } if (options.with_extended_objects) all_columns = extendObjectColumns(all_columns, object_types, options.with_subcolumns); return all_columns; } Block StorageSnapshot::getSampleBlockForColumns(const Names & column_names) const { Block res; auto all_columns = getColumns(GetColumnsOptions(GetColumnsOptions::All) .withSubcolumns().withVirtuals().withExtendedObjects()); std::unordered_map columns_map; columns_map.reserve(all_columns.size()); for (const auto & elem : all_columns) columns_map.emplace(elem.name, elem.type); for (const auto & name : column_names) { auto it = columns_map.find(name); if (it != columns_map.end()) res.insert({it->second->createColumn(), it->second, it->first}); else throw Exception(ErrorCodes::NOT_FOUND_COLUMN_IN_BLOCK, "Column {} not found in table {}", backQuote(name), storage.getStorageID().getNameForLogs()); } return res; } void StorageSnapshot::check(const Names & column_names) const { auto available_columns = getColumns(GetColumnsOptions(GetColumnsOptions::AllPhysical) .withSubcolumns().withVirtuals().withExtendedObjects()).getNames(); if (column_names.empty()) throw Exception(ErrorCodes::EMPTY_LIST_OF_COLUMNS_QUERIED, "Empty list of columns queried. There are columns: {}", boost::algorithm::join(available_columns, ",")); std::unordered_set columns_set(available_columns.begin(), available_columns.end()); std::unordered_set unique_names; for (const auto & name : column_names) { if (columns_set.end() == columns_set.find(name)) throw Exception(ErrorCodes::NO_SUCH_COLUMN_IN_TABLE, "There is no column with name {} in table {}. There are columns: ", backQuote(name), storage.getStorageID().getNameForLogs(), boost::algorithm::join(available_columns, ",")); if (unique_names.end() != unique_names.find(name)) throw Exception(ErrorCodes::COLUMN_QUERIED_MORE_THAN_ONCE, "Column {} queried more than once", name); unique_names.insert(name); } } }