Question

I’m sure this is a common query but I’m not certain how to phrase it best.

I have two tables:

Questions { Id, Text... }
Answers { Id, QuestionId, Text...}

I would like to retrieve a list of Questions and their Answers, so that the results can be displayed like this:

• Question A
  • 1st answer to question A
  • 2nd answer to question A
  • 3rd answer to question A
• Question B
  • 1st answer to question B
    … etc

Assume that there is some selection criteria on the Question table.

A very inefficient method would be to select all the relevant questions, then for each select all the answers. Another inefficient method would be to use a LEFT OUTER JOIN.

What’s the most efficient, simplest way of getting the questions and answers? Can it be done in one query?

Answer 1

For MySQL (not MSSQL) Something like this would work;

SELECT q.text, a.text
FROM questions q
LEFT JOIN answers a ON 
    q.quiestionid = q.id
GROUP BY q.id, a.id
ORDER BY q.id

Let me know if you have any q’s.