Hi Char,
The query fails because it doesn't have single quotes around the string, like this: 'AXT1113'
However, with OpenACS's cool database API, you need not worry about that. Just use bind variables like this:
SELECT book.issue FROM book WHERE book.issue = :issue
SELECT text.textid FROM text WHERE text.textid = :textID
OACS will take care of properly quoting the $issue and $textID variables, including escaping embedded quotes. This is also more secure than embedding variables directly in your query string.
Check out:
https://openacs.org/doc/openacs-4-6-3/db-api.html
https://openacs.org/doc/openacs-4-6-3/db-api-detailed.html
Good luck...