選擇動態列Mysql

Question

我很難搞清楚如何提出這個問題。我有兩個表格，一個是註冊表時間的「訂單」列表，另一個是「活動」表格，我有一個這些訂單製作過程的時間的註冊表。

我沒有得到如何做的是接下來的事情，我需要能夠確定一個查詢自上一個過程以來每個訂單的時間量。

表：Ordenes

| Id | Numero | flujo_id | LastOrder |   FechaRegistro | 
|----|--------|----------|-----------|--------------------------| 
| 1 | 111 |  1 |   0 | August, 13 2015 13:25:00 | 
| 2 | 222 |  1 |   2 | August, 13 2015 13:25:00 | 
| 3 | 333 |  1 |   4 | August, 13 2015 13:25:00 | 
| 4 | 444 |  1 |   3 | August, 13 2015 13:25:00 | 

表：ACTIVIDAD

| Id |    TiempoInicio | TiempoFin | Proceso_Id | Orden_Id | 
|----|--------------------------|-----------|------------|----------| 
| 7 | August, 13 2015 13:30:00 | (null) |   1 |  2 | 
| 8 | August, 13 2015 13:50:00 | (null) |   2 |  2 | 
| 9 | August, 13 2015 13:30:00 | (null) |   1 |  3 | 
| 10 | August, 13 2015 13:50:00 | (null) |   2 |  3 | 
| 11 | August, 13 2015 14:20:00 | (null) |   3 |  3 | 
| 12 | August, 13 2015 14:25:00 | (null) |   4 |  3 | 
| 13 | August, 13 2015 13:30:00 | (null) |   1 |  4 | 
| 14 | August, 13 2015 13:50:00 | (null) |   2 |  4 | 
| 15 | August, 13 2015 14:20:00 | (null) |   3 |  4 | 

表：Procesos

| Id | Estacion_Id |            Nombre |     TiempoStd | 
|----|-------------|----------------------------------------------------|---------------------------| 
| 1 |   1 |  Informacion <br/>tecnica para <br/>aprobacion | January, 01 1970 00:02:00 | 
| 2 |   2 | Aprobacion de<br/> Informacion<br/>Tecnica cliente | January, 01 1970 00:24:00 | 
| 3 |   3 |    Informacion<br/>Tecnica de<br/>Proceso | January, 01 1970 00:04:00 | 
| 4 |   4 |   Compra y<br/>Recepcion de<br/>Materiales | January, 01 1970 02:00:00 | 

的預期輸出。

| Id | Numero |   FechaRegistro | P1 | P2 | P3 | P4 | 
|----|--------|--------------------------|--------|--------|--------|--------| 
| 1 | 111 | August, 13 2015 13:25:00 | (null) | (null) | (null) | (null) | 
| 2 | 222 | August, 13 2015 13:25:00 | 5:00 | 20:00 | (null) | (null) | 
| 3 | 333 | August, 13 2015 13:25:00 | 5:00 | 20:00 | 30:00 | 5:00 | 
| 4 | 444 | August, 13 2015 13:25:00 | 5:00 | 20:00 | 30:00 | (null) | 

什麼我不知道該怎麼做是能夠做到動態調用，這樣我會得到P1，P2，P3，直到光合速率列N =上「Procesos」表中的行數。而對於時間計算我確實有一個想法，但因爲我不知道如何得到這些列我不能嘗試它。

這是一張裝載表格的小提琴。 HERE

Answer 1

我想出了下面的東西。它可能看起來不太模糊。

select ordenes.Id,Numero,FechaRegistro,m.p1,a.p2,b.p3,c.p4 from Ordenes 
left join (select ordenes.id, 
       TIMESTAMPDIFF(MINUTE,Ordenes.FechaRegistro,min(Actividad.TiempoInicio)) P1 
      from Ordenes 
      left join Actividad on ordenes.id=Actividad.orden_id 
      group by Actividad.orden_id) as m on ordenes.id=m.id 
left join (select Orden_Id,TIMESTAMPDIFF(MINUTE,min(TiempoInicio),max(TiempoInicio)) P2 
      from actividad 
      where Proceso_Id in ('1','2') 
      group by orden_id) as a on ordenes.id=a.orden_id 
left join 
(select Orden_Id,TIMESTAMPDIFF(MINUTE,min(TiempoInicio),max(TiempoInicio)) P3 
     from actividad 
     where Proceso_Id in ('2','3') 
     group by orden_id) as b on ordenes.id=b.orden_id 
left join 
(select Orden_Id,TIMESTAMPDIFF(MINUTE,min(TiempoInicio),max(TiempoInicio)) P4 
     from actividad 
     where Proceso_Id in ('3','4') 
     group by orden_id) as c on ordenes.id=c.orden_id 
order by id; 

輸出我得到

| Id | Numero |   FechaRegistro | P1 | P2 | P3 | P4 | 
|----|--------|--------------------------|--------|--------|--------|--------| 
| 1 | 111 | August, 13 2015 13:25:00 | (null) | (null) | (null) | (null) | 
| 2 | 222 | August, 13 2015 13:25:00 | 5  | 20  | 0  | (null) | 
| 3 | 333 | August, 13 2015 13:25:00 | 5  | 20  | 30  | 5  | 
| 4 | 444 | August, 13 2015 13:25:00 | 5  | 20  | 30  | 0  | 

它不符合所有要求。但ATLEAST作爲參考，以進一步

DEMO Fiddle