select from one table, count from another where id's linked

Question

heres my code:

$sql = mysql_query(\"select c.name, c.address, c.postcode, c.dob, c.mobile, c.email, 
                    count(select * from bookings where b         


        

Answer 1

Your query incorrectly uses COUNT, which has been covered by @Will A's answer.

I would also like to suggest a possibly better constructed alternative, which, I think, reflects the same logic:

SELECT
  c.name,
  c.address,
  c.postcode,
  c.dob,
  c.mobile,
  c.email,
  COUNT(*) AS purchased,
  COUNT(b.the_date > $now OR NULL) AS remaining
FROM customers AS c
  INNER JOIN bookings AS b ON b.id_customer = c.id
GROUP BY c.id
ORDER BY c.name ASC

Note: Normally you are expected to include all the non-aggregated SELECT expressions into GROUP BY. However MySQL supports shortened GROUP BY lists, so it's enough to specify the key expressions that uniquely identify all the non-aggregated data you are pulling. Please avoid using the feature arbitrarily. If a column not included in GROUP BY has more than one value per group, you have no control over which value will actually be returned when pulling that column without aggregation.

Answer 2

Try changing the likes of...

count(select * from bookings where b.id_customer = c.id)

...to...

(select count(*) from bookings where b.id_customer = c.id)