Php 多个SQL Select和Where在同一个表上

我需要对MYSQL数据库中的一个表进行查询。在这个查询中，我需要使用不同的where进行多个选择

我目前的查询是：

$result = mysql_query("
    SELECT
        last_name, first_name, user_name,
        SUM(rthours) as rthours, SUM(othours) as others,
        SUM(trthours) as trthours, SUM(tothours) as tot hours
    FROM data
    WHERE labor_date BETWEEN '$start' AND '$end'
    ORDER BY last_name ASC
");

我还需要选择以下两项：

SUM(rthours) as vhours FROM data WHERE decription = 'vacation' AND labor_date BETWEEN '$start' AND '$end'

及

如何将所有三个选择组合到一个查询中，以便在随后输出的表中使用它们

---

谢谢你的帮助

您可以使用

联合所有
。它将多个查询的结果组合成一个结果集

查找：
您可以在
SUM（）中使用
CASE

对于聚合函数，您应该使用组函数，这将是一个混乱，但您可以将其作为子查询运行：

SELECT last_name, first_name, user_name, SUM(rthours) as rthours,
SUM(othours) as othours, SUM(trthours) as trthours, 
SUM(tothours) as tothours, 
(SUM(rthours) as vhours FROM data WHERE decription = 'vacation' AND labor_date BETWEEN '$start' AND '$end') AS vhours
(SUM(rthours) as shours FROM data WHERE decription = 'sick' AND labor_date BETWEEN '$start' AND '$end') AS shours
FROM data WHERE labor_date BETWEEN '$start' AND '$end' Order by last_name ASC

我无法运行这些，因为我没有表格或数据，但重要的是它的基本思想得到了它

这项工作：

$result = mysql_query("SELECT last_name, first_name,
SUM(CASE WHEN description = 'Vacation' THEN rthours ELSE 0 END) as vhours,
SUM(CASE WHEN description = 'Sick' THEN rthours ELSE 0 END) as shours,   
SUM(rthours) as rthours,
SUM(othours) as othours,
SUM(trthours) as trthours, 
SUM(tothours) as tothours
FROM data 
WHERE labor_date BETWEEN '$start' AND '$end' Group by last_name Order by last_name ASC");

谢谢你的帮助
 这在使用时不返回任何记录。这应该是因为表中的数据符合select语句的要求。经过一些研究，我将上面的代码编辑为：
$result=mysql\u query（“选择姓氏、姓氏、总和（说明时的大小写为“休假”，然后为rthours ELSE 0 END）作为vhours、SUM（说明时的大小写为“生病”，然后为rthours ELSE 0 END）作为应付款，SUM（othours）为othours，SUM（trthours）为trthours，SUM（TOTHHOURS）为TOTHHOURS，根据姓氏ASC，从“开始日期”到“结束日期”之间的数据计算得出
但它仍然不返回任何结果。@Lawrence您是否可以添加带有样本数据集的表，这样在使用时更容易识别它不返回任何记录。由于表中的数据符合select语句的要求，因此应进行修改。
SELECT last_name, first_name, user_name, SUM(rthours) as rthours,
SUM(othours) as othours, SUM(trthours) as trthours, 
SUM(tothours) as tothours, 
(SUM(rthours) as vhours FROM data WHERE decription = 'vacation' AND labor_date BETWEEN '$start' AND '$end') AS vhours
(SUM(rthours) as shours FROM data WHERE decription = 'sick' AND labor_date BETWEEN '$start' AND '$end') AS shours
FROM data WHERE labor_date BETWEEN '$start' AND '$end' Order by last_name ASC

$result = mysql_query("SELECT last_name, first_name,
SUM(CASE WHEN description = 'Vacation' THEN rthours ELSE 0 END) as vhours,
SUM(CASE WHEN description = 'Sick' THEN rthours ELSE 0 END) as shours,   
SUM(rthours) as rthours,
SUM(othours) as othours,
SUM(trthours) as trthours, 
SUM(tothours) as tothours
FROM data 
WHERE labor_date BETWEEN '$start' AND '$end' Group by last_name Order by last_name ASC");