**Use case**
A friend wants to show me a set of queries, but is afraid to reveal the names of columns (domain area) and the values of constants.

**Describe the solution you'd like**
A simple ad-hoc solution that will be mostly acceptable.

Use Lexer to tokenize query and replace tokens. Use a list of english nouns or similar words for replacements. The user will specify a salt in command line to make deterministic pseudorandom unpredictable replacement.

Split identifiers to words according to their style (snake_case, CamelCase, ALL_CAPS). If identifier is too complex, treat it as a single word. These words will be replaced with english nouns selected by the value of a SipHash from the word and the salt. Save all replacements in a map to track collisions. In case of collision, add 1 to the salt and repeat to select another noun. Keep the style of replaced identifiers for convenience. Keep some words like `id`, `num`, `value` unreplaced.

For literals in a query: for numbers, dates, datetimes, apply a model similar to clickhouse-obfuscator. For string literals, keep punctuation charaters as is to keep the meaning of LIKE and regexp. Replace alphanumeric parts to a gibberish of similar length (maybe keeping alpha and numerics). Replace valid UTF-8 to another valid UTF-8 while keeping the number of leading zeros in bytes.

Keep the keywords in the query as is. (Lexer does not know about keywords, so we have to list them explicitly).
{
            std::cerr << "Options 'hilite' or 'oneline' have no sense in 'quiet' mode." << std::endl;
            return 2;
        }
        String query;
        ReadBufferFromFileDescriptor in(STDIN_FILENO);
        readStringUntilEOF(query, in);
        const char * pos = query.data();
        const char * end = pos + query.size();
        ParserQuery parser(end);
        do
        {
            ASTPtr res = parseQueryAndMovePosition(parser, pos, end, "query", multiple, 0, DBMS_DEFAULT_MAX_PARSER_DEPTH);
            if (!quiet)
            {
                formatAST(*res, std::cout, hilite, oneline);
                if (multiple)
                    std::cout << "\n;\n";
                std::cout << std::endl;
            }
        } while (multiple && pos != end);
    }
    catch (...)
    {
        std::cerr << getCurrentExceptionMessage(true);
        return getCurrentExceptionCode();
    }
    return 0;
}