MySQL数据显示而不是一行多行

Question

我想知道如何根据字段值我没有的情况下，选择显示上述数据成一排，但它的未来，如下图

(SELECT lead_id, 
case lead_id 
case field_number when 1 then value end as firstname 

case field_number when 1 then value end as firstname, 
case field_number when 2 then value end as lastname, 
case field_number when 10 then value end as email, 

Answer 1

您正在试图用条件汇总（这意味着你被子句缺少组的最大/最小功能）做到这一点：

SELECT lead_id, 
     MAX(CASE WHEN field_number = 1 then value end) as firstname, 
     MAX(CASE WHEN field_number = 2 then value end) as lastname, 
     MAX(CASE WHEN field_number = 10 then value end) as email 
FROM YourTable 
GROUP BY lead_id