MySQL query with LEFT OUTER JOIN and WHERE

Question

I have three tables: stories , story_types , and comments

The following query retrieves all of the records in the stories table, gets their story_types , and the number of comments associated with each story:

         SELECT s.id AS id,
                s.story_date AS datetime,
                s.story_content AS content,
                t.story_type_label AS type_label,
                t.story_type_slug AS type_slug,
                COUNT(c.id) AS comment_count
           FROM stories AS s
LEFT OUTER JOIN story_types AS t ON s.story_type_id = t.id
LEFT OUTER JOIN comments AS c ON s.id = c.story_id 
       GROUP BY s.id;

Now what I want to do is only retrieve a record from stories WHERE s.id = 1 (that's the primary key). I have tried the following, but it still returns all of the records:

         SELECT s.id AS id,
                s.story_date AS datetime,
                s.story_content AS content,
                t.story_type_label AS type_label,
                t.story_type_slug AS type_slug,
                COUNT(c.id) AS comment_count
           FROM stories AS s
LEFT OUTER JOIN story_types AS t ON s.story_type_id = t.id
                AND s.id = 1
LEFT OUTER JOIN comments AS c ON s.id = c.story_id 
       GROUP BY s.id;

I have also tried a WHERE clause at the end, which throws an error.

Can someone point out the correct syntax for a condition like this in this situation?

I'm using MySQL 5.1.47. Thanks.

Answer 1

I'm guessing you put the WHERE after the GROUP BY, which is illegal. See this reference on the SELECT syntax in MySQL. Try this:

SELECT
    s.id AS id,
    s.story_date AS datetime,
    s.story_content AS content,
    t.story_type_label AS type_label,
    t.story_type_slug AS type_slug,
    COUNT(c.id) AS comment_count
FROM
    stories AS s
    LEFT JOIN story_types AS t ON s.story_type_id = t.id
    LEFT JOIN comments AS c ON s.id = c.story_id 
WHERE
    s.id = 1
GROUP BY
    s.id;

editor's note: I reformatted the code to highlight the query structure

Answer 2

Following up this comment on the accepted answer:

It is not intuitive to me that this WHERE would go in the second JOIN

This is just to outline how proper code formatting enhances understanding. Here is how I usually format SQL:

SELECT 
  s.id               AS id,
  s.story_date       AS datetime,
  s.story_content    AS content,
  t.story_type_label AS type_label,
  t.story_type_slug  AS type_slug,
  COUNT(c.id)        AS comment_count
FROM 
  stories                  AS s
  LEFT JOIN story_types    AS t ON t.id = s.story_type_id 
  LEFT OUTER JOIN comments AS c ON s.id = c.story_id 
WHERE
  s.id = 1
GROUP BY
  s.id;

The WHERE is not on the second join. There is only one WHERE clause allowed in a SELECT statement, and it always is top level.

PS: Also note that in many database engines (apart from MySQL) it is illegal to use a GROUP BY clause and then selecting columns without aggregating them via functions like MIN() , MAX() , or COUNT() . IMHO this is bad style and a bad habit to get into.