Function validateGroupByKeyType

src/DataTypes/validateGroupByKeyType.cpp:13–31

}

void validateGroupByKeyType(const DataTypePtr & key_type, bool allow_suspicious_types)
{
    if (allow_suspicious_types)
        return;

    auto check = [](const IDataType & type)
    {
        if (isDynamic(type) || isVariant(type))
            throw Exception(
                ErrorCodes::ILLEGAL_COLUMN,
                "Data types Variant/Dynamic are not allowed in GROUP BY keys, because it can lead to unexpected results. "
                "Consider using a subcolumn with a specific data type instead (for example 'column.Int64' or 'json.some.path.:Int64' if "
                "its a JSON path subcolumn) or casting this column to a specific data type. "
                "Set setting allow_suspicious_types_in_group_by = 1 in order to allow it");
    };

    check(*key_type);
    key_type->forEachChild(check);
}

}