Can SELECT be nested as

I know you can do something like:

SELECT
ColumnA,

(SELECT Columnb FROM Table Where...),

ColumnC
...

Can you select multiple columns, and how if possible, such as:

SELECT
ColumnA,

(SELECT ColumnB, ColumnC, ColumnD FROM Table Where...),

ColumnE
...

If this is possible, how would the columns be aliased?

Thanks in advance.no, you can't do that, sorry

in the SELECT list, you can have only scalar subqueries, i.e. that return only one value -- one row, one column, one value|||...and just because your first example CAN be done, doesn't mean it SHOULD be done. TSQL has this little concept called a JOIN...|||I am well aware of the JOIN, and the sarcasm isn't appreciated. The
tools included with Enterprise Manager haven't helped identify or
resolve this issue.

There are several columns identified in certain tables that cause the
query time to go from an acceptable 10 seconds to 40 seconds when added
to the SELECT statement. Each column added increases the time until
the query time is over 8 minutes which is unacceptable.

The columns are from a table that is already included in the query. We are not adding another table/join when selecting these columns. The column
data types are NVARCHAR(40) and are not included in the WHERE clause.

The only solution found so far is adding the columns as nested SELECT
statements (all 15 of them) as shown in my original post. This is a
real mess, but the client doesn't care as long as he gets the
performance boost.

Any ideas?

JRA|||ideas? yes, i would use joins and ensure that the join columns are properly indexed|||I don't think indexes are the issue. Adding a single column from a
table that's already in the query causes a massive decrease in
performance. IE:

SELECT
TblA.ColumnA,
TblB.ColumnC
FROM
TableA TblA,
TableB TblB
WHERE
TblA.ID = TblB.ID

The above runs in 10 seconds. The version below runs in 40 seconds.

SELECT
TblA.ColumnA,
TblA.ColumnB,
TblB.ColumnC
FROM
TableA TblA,
TableB TblB
WHERE
TblA.ID = TblB.ID

If we add another column from TableA the query time junps by 30
seconds. Nothing is added except a column. Why would indexes affect
this situation? I don't think they would.|||is the column being added a text field? that would be a significant increase in bandwidth and explain the decrease in performance|||Why are people asking for free help these days so sensitive? Lighten up!

I'm taking my sarcasm (and advice) and going home. Your client is paying you, so YOU figure it out.|||OK, I've run out of sarcasm, so here is a suggestion:

If you have what is known as a "covered index" on table A that includes both ColumnA and ID, then your first query is never actually accessing the data in Table A, because it can get all the info it needs just from the index alone. Adding in another field requires the server to actually look up that value in table A based upon the index value, and that takes additional time.
So if this is the case, then its not that your second query is abnormally slow, but rather that SQL Server is able to process your first query extremely efficiently.