作者s900527 (水)
看板PHP
標題[請益] 拜託指點一SQL查詢order by 的問題
時間Thu Jan 11 18:02:42 2007
$sql = "select r.id,m.name,count(*),SUM(r.amnt) as ammount FROM member as m , rent as r WHERE r.id = '".$id."' and r.id = m.id group by id order by ammount DESC";
// select c.bookid,c.title,count(*),sum(r.amnt) as ammount from rent as r
// here and r.bookid=c.bookid and r.id=m.id group by c.bookid order by ammount desc";
$a = mysql_query($sql);
while(list($aid,$name,$count,$sum)=mysql_fetch_row($a))
{
echo "<tr>";
echo "<td>$aid</td>";
echo "<td>$name</td>";
echo "<td>$count</td>";
echo "<td>$sum</td>";
echo "</tr>";
$total += $sum;
}
}
這是我的程式碼想讓他最後按照$sum的大小遞減排序
可是卻沒辦法
不知道是哪邊出了錯誤
拜託各位大大指點一下
感激不盡
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1F：推 thitbbeb:order by 後面改成SUM(r.amnt)試試= = 01/11 18:13
2F：推 s900527:我有試過改那樣不過他會顯示查詢語法錯誤說@@ 01/11 18:46
3F：推 thitbbeb:我想問你count(*)要做啥用的= =?會不會是它的關係~刪掉試 01/11 20:36
4F：→ thitbbeb:還有你這是二個資料表關聯嗎?m.id=r.id?為啥不用join? 01/11 20:37
5F：推 s900527:count是因為要計算他的次數~@@我要判斷他每本書的出現次數 01/12 01:56
6F：→ s900527:兩個資料表示關聯查詢的@@join是什麼阿我不會耶= = 01/12 01:57
7F：推 wa120:mysql之前用過"欄位"不能跟count()放在一起 01/12 18:35