在MySQL查询中一起使用MAX和COUNT

Question

I'm new in mysql. I have 2 mysql tables, company and info . The 1st table has cid, name, classification, address, city, phone, province and the 2nd table has cid, information dan infodate . They are relational where company.cid=info.cid. I have used

SELECT *, MAX(infodate)
FROM company
JOIN info ON company.cid = info.cid
WHERE classification = 'Hotel'
GROUP BY name
ORDER BY MAX(infodate) DESC
LIMIT 0,7

I want to add COUNT in that statement so each company will have sum of informations to display. Thank you.

Answer 1

Try this

SELECT SQL_CALC_FOUND_ROWS *, MAX(infodate)
FROM company
JOIN info ON company.cid = info.cid
WHERE classification = 'Hotel'
GROUP BY name
ORDER BY MAX(infodate) DESC
LIMIT 0,7

And then, to retrieve the count use

$total = mysql_fetch_row(mysql_query("SELECT FOUND_ROWS()"));
$total = $total[0];

Answer 2

Try this

SELECT company.*, COUNT(info.information) 
    FROM company JOIN info ON company.cid = info.cid
    WHERE classification = 'Hotel'
    GROUP BY company.cid
    ORDER BY MAX(info.infodate) DESC
    LIMIT 0,7

Answer 3

如果执行此操作会发生什么：

SELECT *, MAX(infodate), COUNT(*) as count