SQL多结果问题

Question

我可以使用单个SQL语句返回我可以通过PHP显示的三个单独结果吗？我希望在一个有三种不同条件的桌子上制定三种不同的“总数”。

例如..... ......

$resultGetTotals = SELECT COUNT(Total1) FROM table_xyz WHERE Status = X AS Total1
SELECT COUNT(Total2) FROM table_xyz WHERE Status = X AND Person = Y AS Total2
SELECT COUNT(Total3) FROM table_xyz WHERE Status = Y AND Person = X AS Total3

while ($rGetTotals = mysql_fetch_array($resultGetTotals)){
$Total1 = $rGetTotals["Total1"]
$Total2 = $rGetTotals["Total2"]
$Total2 = $rGetTotals["Total2"];
}

Total One is: <?php print $Total1; ?><br>
Total Two is: <?php print $Total2; ?><br>
Total Three is: <?php print $Total3; ?><br>

任何帮助都非常感谢：）

Answer 1

SQL：

SELECT SUM(CASE WHEN t.status = X THEN 1 ELSE 0 END) AS total1,
       SUM(CASE WHEN t.status = X AND t.person = Y THEN 1 ELSE 0 END) AS total2,
       SUM(CASE WHEN t.status = Y AND t.person = X THEN 1 ELSE 0 END) AS total3
  FROM TABLE_XYZ t

PHPified：

$result = mysql_query("SELECT SUM(CASE WHEN t.status = X THEN 1 ELSE 0 END) AS total1,
                              SUM(CASE WHEN t.status = X AND t.person = Y THEN 1 ELSE 0 END) AS total2,
                              SUM(CASE WHEN t.status = Y AND t.person = X THEN 1 ELSE 0 END) AS total3
                         FROM TABLE_XYZ t");

while ($row = mysql_fetch_array($result)) {
 echo "Total One is: $row['total1']<br>"
 echo "Total Two is:  $row['total2']<br>"
 echo "Total Three is:  $row['total3']<br>"
}

mysql_free_result($result);

Answer 2

假设您想要每个用户的行数（而不是三个不同列中的非空值的数量），然后是所有用户，并进一步假设表中只有Person X和Y，使用方法：

SELECT Person, COUNT(*) FROM table_xyz GROUP BY Person

检索两个总计（对于人X和人Y）并将它们加在一起以获得总计。