SQL-ORDER BY在子查询中有效，但在完整查询中失败

Question

I'm trying to set up a dynamic query to populate average payments over a dynamic period of months. I have a working query, but it provides the months out of order.

I assign the months to a variable, @columns, and use that in the main query to determine the fields for a PIVOT command. The following is how the variable is set up;

As can be seen, the months are out of order.

But, if I run just the sub-query;

It orders fine.

What's going on? Any thoughts?

Thanx in advance!

(hopefully, the images come out as I want)

Answer 1

In your outer select you need to specify ORDER BY to guarantee the order. Currently you are only ordering your derived table and not the final query.

SELECT @columns += ',' + QUOTENAME(Eff_Period)
FROM
  (derived table) AS Raw_Data
ORDER BY Eff_Period

PRINT @columns

Answer 2

 SELECT @columns == ',' + QUOTENAME (Eff_period)
 FROM ( ... ) as Raw_Data
 ORDER BY Eff_period

Answer 3

I think the subquery is unnecessary if all you need additionally is to concatenate the text ',' + + QUOTENAME(Eff_Period) . But you can just do this without a subquery. Also, the TOP 100 PERCENT does not work as others have pointed out, it's not needed in any case.

SELECT @column += ',' + QUOTENAME(Eff_Period)
  FROM Members_Data AS Mbrs
       INNER JOIN Claims_Data AS Clms
        ON Mbrs.Eff_Period = REPLACE(CONVERT(nvarchar(7), Clms.Date_of_Service, 121), '-', '')
 WHERE YEAR(Clms.Date_of_Service) = 2016

GROUP BY Mbrs.Eff_Period
ORDER BY Eff_Period

Also... I had to re-type the entire text from the screenshot. Not a big deal to some people, but this is one reason we prefer the text versus screenshot.

Answer 4

Yes, the outside ORDER BY was the answer.

I thought ORDER BY had to use field names and, as there was none, I had no clue how to put it in there. I tried using the ordinal, 1, unfortunately that only gave me the final value in the concatenated list.

But, it appears that it can take Eff_Period in the outside SELECT ; perhaps because it's a unique name from the JOIN .

However, that answered the problem I was having. A problem that arose from an answer that I thought fixed an overlying problem, but I have discovered does not. I'm trying to figure that out at this time.

Thanx to everyone who responded!