dongzuoyue6556 2013-12-01 20:01
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如何使用mysql和php计算每个州的总条目数

I have a table "data" with a column "name" "state" and a few more

name     state
peter     MN
john      NY
jay       NY
sam       CO
jack      TX
jill      NO

I want to calculate the number of entries per state and want my output as follows for example:

NY: 125
MN: 21
CO: 17
TX: 10
NO: 59

etc...

I have a query like this

$stmt = $db->query("SELECT state, COUNT(*) FROM `data` GROUP BY state;");
$nums = $stmt->rowCount();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)){
echo "<tr>
       <td>" . $row["state"] . "</td>
       <td>$nums</td>
     </tr>";
}

This displays every state in my table but does not return the corresponding number of entries for that state. This only returns the number of states i.e. 50. How can I display the number of entries per state?

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2条回答 默认 最新

  • duanque3125 2013-12-01 20:08
    关注

    You seem not to be referring to the column which has the count. Try aliasing it an referencing the alias in your PHP code:

    $stmt = $db->query("SELECT state, COUNT(*) cnt FROM `data` GROUP BY state;");
    while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
        echo "<tr>
           <td>" . $row["state"] . ":</td>
           <td>" . $row["cnt"] . "</td>
         </tr>";
    }
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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