Question

我想选择按订单数量分组的客户数量。结果应该是这样的：

use HTML::HTMLDoc;
my $htmldoc = new HTML::HTMLDoc;
$htmldoc->set_html_content(<<"EOF");
<html><body>   
This is my <b>pdf</b>...
</body></html>
EOF

$htmldoc->set_bodyimage('bg.png');
print $htmldoc->generate_pdf()->to_string();

我不知道该怎么做

Number of Orders | Numbers of Customers
---------------------------------------
1                |  29
2                |  16
3                |  23
4                |  26
....

感谢您的帮助。

Answer 1

如果我理解正确的话：

SELECT s.num_of_orders,count(*) as num_of_customers
FROM(
    SELECT count(*) as num_of_orders
    FROM Orders o
    GROUP BY o.customer_id) s
GROUP BY s.num_of_orders

选择按订单数量分组的客户数量

1 个答案: