Question

I have the following script and would like to change it so that it agrees with the international standards. I use SQL-Server but whenever possible I’d like to follow the international standards for SQL. I don’t believe that the square brackets are standard – should I replace them with double quotes?

Without paying to get a copy of the standards document are there any resources on the internet which give examples of scripts formatted and laid out exactly as required by the standards?

SELECT 
    a.UserAccountKey,
    SUM(ISNULL(b.[measure Y],0.0)) AS "measure Y",
    SUM(ISNULL(c.[measure Z],0.0)) AS "measure Z"
FROM 
    XXX a
    LEFT OUTER JOIN YYYY b ON
        a.UserAccountKey = b.UserAccountKey
    LEFT OUTER JOIN ZZZZ c ON
        a.UserAccountKey = c.UserAccountKey
GROUP BY
    a.UserAccountKey

---

EDIT

My only slight preference that is not classic standard is the following. This was put forward by AaronBertrand and I agree that it’s more readable – especially if the SELECT clause has 20 or 30 fields:

SELECT 
    a.UserAccountKey,
    "measure Y"             = SUM(ISNULL(b."measure Y",0.0)),
    "measure Z"             = SUM(ISNULL(c."measure Z",0.0)),
    "measure longertitle"   = SUM(ISNULL(c."measure longertitle",0.0)),
    "me short"              = SUM(ISNULL(c."me short",0.0))
FROM 

Answer 1

Change ISNULL to COALESCE and square brackets to " and then it validates.

SELECT a.UserAccountKey,
       SUM(COALESCE(b."measure Y", 0.0)) AS "measure Y",
       SUM(COALESCE(c."measure Z", 0.0)) AS "measure Z"
FROM   XXX a
       LEFT OUTER JOIN YYYY b
         ON a.UserAccountKey = b.UserAccountKey
       LEFT OUTER JOIN ZZZZ c
         ON a.UserAccountKey = c.UserAccountKey
GROUP  BY a.UserAccountKey; 

This does mean that you need to ensure that QUOTED_IDENTIFIER is ON in SQL Server.