Mysql Group BY with if语句

Question

我不确定这是否可以在没有嵌套选择的单个select语句中执行。

我将我的结果分组，并且我想知道如果整个分组内的字段包含条件，则显示yes。有了这个就只取第一行从组和检查车况而不是组

if(field = 'condition','yes','no') as field_found 

Answer 1

例如表中的所有行：ID，得分

SELECT t1.id, (
    SELECT IF("10" IN (
    SELECT score FROM table t2 WHERE t1.id = t2.id 
),'yes','no')) 
FROM table t1 
GROUP BY t1.id 

运作的？

Answer 2

if(GROUP_CONCAT(field) LIKE '%condition%','yes','no') 

SELECT first_name,last_name, CONCAT(physical_address," ",physical_address2," ",city, " ",zip) as address, MONTHNAME(install_date) as billing_month, IFNULL(status.quantity,0) as total_measures_instalclient2d,IFNULL(client1_measures,"") as client1_measures,IFNULL(client2_measures,"") as client2_measures,IFNULL(client1_quantity,0) as client1_quantity,IFNULL(client2_quantity,0) as client2_quantity,if(GROUP_CONCAT(measure_list.measure_type) LIKE '%Outreach/ Assessment%','yes','no') as outreach_invoiced,GROUP_CONCAT(IF(client='Client1',CONCAT(percent*100,"%-",measure_list.measure_type),NULL)) as client1_percent,GROUP_CONCAT(IF(client='Client2',CONCAT(percent*100,"%-",measure_list.measure_type),NULL)) as client2_percent,work_order.notes FROM customers 
INNER JOIN measure on measure.customer_id = customers.customer_id 
INNER JOIN measure_list on measure_list.measure_list_id = measure.measure_list_id 
INNER JOIN work_order on work_order.work_order_id = measure.work_order_id 
INNER JOIN billing on billing.workmanship = work_order.workmanship AND billing.measure_type = measure_list.measure_type 
LEFT JOIN (
SELECT customers.customer_id,SUM(quantity) as quantity,GROUP_CONCAT(IF(client='Client1',measure_description,NULL)) as client1_measures,GROUP_CONCAT(IF(client='client2',measure_description,NULL)) as client2_measures,SUM(IF(client='client1',quantity,0)) as client1_quantity,SUM(IF(client='client2',quantity,0)) as client2_quantity FROM customers 
INNER JOIN measure on measure.customer_id = customers.customer_id 
INNER JOIN measure_list on measure_list.measure_list_id = measure.measure_list_id 
INNER JOIN work_order on work_order.work_order_id = measure.work_order_id 
INNER JOIN billing on billing.workmanship = work_order.workmanship AND billing.measure_type = measure_list.measure_type 
WHERE measure_list.measure_type NOT IN ('measure1','measure2') 
GROUP BY customers.customer_id 
) as status on status.customer_id = customers.customer_id 
WHERE measure_list.measure_type IN ('measure1','measure2') 
GROUP BY customers.customer_id 

Answer 3

既然你已经做一组，你应该能够添加MAX（）为具有条件你期望，只是添加到该组列...如

select 
     MAX(if(field LIKE '%condition%','1', '2')) as ExtraOrderBy, 
     First_Name, 
     Last_Name, 
     ... rest of query ... 
    group by 
     customers.Customer_ID 
    order by 
     1 

在这种情况下，order by是SQL列表中的有序列，而不是显式重新输入MAX（IF（））条件...因此，如果条件为真，则用“1”标记它，否则“2”会将所有符合条件的列表浮动到列表顶部......然后，您可以通过其他方式（例如姓氏，名字或其他您所查询的字段）进行子命令。