- The reserved-words branch had a bug: MySQL's default escaping character is actually ` (backtick), not " (double quote). The bug went unnoticed because MySQL understands double quotes as strings, and it accepts strings in places such as aliases (e.g. foo as "str"). - A new test was introduced to verify that quoting actually works in all backends. - This change also inverts the logic for deciding when to quote. Rather than looking for unaccepted characters, we quote anything that doesn't look like a nice word ([a-z][a-z0-9_]+).