如何在mysql中打印計數值？

Question

查詢：

$query=mysql_query(SELECT content_id, COUNT(*) FROM votingapi_vote WHERE value_type = option AND value = 1 GROUP BY content_id) 

，如果我把它分配給$result。

while ($obj = db_fetch_object ($result)) { 
    $output .= $obj->content_id.'<br>' . $obj->count; 
} 

如何輸出計數值？之後的$obj->content_id。沒有打印號碼。謝謝。

Answer 1

你需要一個別名爲您列COUNT(*)（即重命名列）：

SELECT content_id, COUNT(*) as count FROM [...] 

然後使用變量：

$obj->count 

Answer 2

$query=mysql_query(SELECT content_id, COUNT(*) as count FROM votingapi_vote WHERE value_type = option AND value = 1 GROUP BY content_id) 

Answer 3

給這個算一個別名，像：

SELECT content_id, COUNT(*) as the_count FROM ... 

那麼你可以參考它由名稱：

$output .= $obj->content_id.'<br>' . $obj->the_count;  

Answer 4

變化

COUNT(*) FROM 

到

COUNT(*) as count FROM 

Answer 5

嘗試增加：$查詢=請求mysql_query（選擇的content_id，COUNT（* ）* as the_count * FROM votingapi_vote WHERE value_type = option AND value = 1 GROUP BY content_id）

然後計數應該在$ obj-> the_count