ORDER BY with alias

Hi NG,
in my following query I get the error "Invalid column name 'price'" but
everything seems ok:
SELECT row_number() over (order by price) as row_num,
dbo.getProductPrice('1234') as price
MS describes the use of aliases in ORDER BY
http://msdn2.microsoft.com/ms188385.aspx
Any ideas?
Thanks
Andre ScheiberleAndre Scheiberle wrote:
> Hi NG,
> in my following query I get the error "Invalid column name 'price'" but
> everything seems ok:
> SELECT row_number() over (order by price) as row_num,
> dbo.getProductPrice('1234') as price
> MS describes the use of aliases in ORDER BY
> http://msdn2.microsoft.com/ms188385.aspx
> Any ideas?
> Thanks
> Andre Scheiberle
ORDER BY in a query is different to ORDER BY in a ranking function. In
the latter case you can only reference base columns, not aliases. Try
the following (I assume you omitted the FROM clause in error).
SELECT ROW_NUMBER() OVER (ORDER BY price) AS row_num, price
FROM
(SELECT dbo.getProductPrice('1234')
FROM tbl) AS T(price) ;
David Portas, SQL Server MVP
Whenever possible please post enough code to reproduce your problem.
Including CREATE TABLE and INSERT statements usually helps.
State what version of SQL Server you are using and specify the content
of any error messages.
SQL Server Books Online:
http://msdn2.microsoft.com/library/ms130214(en-US,SQL.90).aspx
--|||does dbo.getProductPrice('1234')
return a table or a scalar value?
--
"Andre Scheiberle" wrote:

> Hi NG,
> in my following query I get the error "Invalid column name 'price'" but
> everything seems ok:
> SELECT row_number() over (order by price) as row_num,
> dbo.getProductPrice('1234') as price
> MS describes the use of aliases in ORDER BY
> http://msdn2.microsoft.com/ms188385.aspx
> Any ideas?
> Thanks
> Andre Scheiberle
>|||ok, in this example it works, but in my Application I use this Query:
SELECT ROW_NUMBER() OVER (ORDER BY price) AS row_num, price, article
FROM
products,
(SELECT dbo.getProductPrice(products.article)M tbl) AS T(price) ;
Now an error appears "The multi-part identifier "products.article" could not
be bound."
Thanks
Andre
"David Portas" wrote:

> Andre Scheiberle wrote:
> ORDER BY in a query is different to ORDER BY in a ranking function. In
> the latter case you can only reference base columns, not aliases. Try
> the following (I assume you omitted the FROM clause in error).
> SELECT ROW_NUMBER() OVER (ORDER BY price) AS row_num, price
> FROM
> (SELECT dbo.getProductPrice('1234')
> FROM tbl) AS T(price) ;
> --
> David Portas, SQL Server MVP
> Whenever possible please post enough code to reproduce your problem.
> Including CREATE TABLE and INSERT statements usually helps.
> State what version of SQL Server you are using and specify the content
> of any error messages.
> SQL Server Books Online:
> http://msdn2.microsoft.com/library/ms130214(en-US,SQL.90).aspx
> --
>|||The table return a scalar value
"Omnibuzz" wrote:
> does dbo.getProductPrice('1234')
> return a table or a scalar value?
> --
>
>
> "Andre Scheiberle" wrote:
>|||try this then.
SELECT ROW_NUMBER() OVER (ORDER BY price) AS row_num, price, article
from
(SELECT dbo.getProductPrice(article), article
FROM
products) AS T(price, article)
"Omnibuzz" wrote:
> does dbo.getProductPrice('1234')
> return a table or a scalar value?
> --
>
>
> "Andre Scheiberle" wrote:
>|||Andre Scheiberle wrote:
> ok, in this example it works, but in my Application I use this Query:
> SELECT ROW_NUMBER() OVER (ORDER BY price) AS row_num, price, article
> FROM
> products,
> (SELECT dbo.getProductPrice(products.article)M tbl) AS T(price) ;
> Now an error appears "The multi-part identifier "products.article" could n
ot
> be bound."
> Thanks
> Andre
>
You can't reference a table from the outer query in a derived table
subquery. Try this (assuming your function is scalar):
SELECT ROW_NUMBER() OVER (ORDER BY price) AS row_num,
price, article
FROM
(SELECT dbo.getProductPrice(article), article
FROM products) AS T(price,article) ;
David Portas, SQL Server MVP
Whenever possible please post enough code to reproduce your problem.
Including CREATE TABLE and INSERT statements usually helps.
State what version of SQL Server you are using and specify the content
of any error messages.
SQL Server Books Online:
http://msdn2.microsoft.com/library/ms130214(en-US,SQL.90).aspx
--|||Here is how a SELECT works in SQL ... at least in theory. Real
products will optimize things, but the code has to produce the same
results.
a) Start in the FROM clause and build a working table from all of the
joins, unions, intersections, and whatever other table constructors are
there. The <table expression> AS <correlation name> option allows you
give a name to this working table which you then have to use for the
rest of the containing query.
b) Go to the WHERE clause and remove rows that do not pass criteria;
that is, that do not test to TRUE (i.e. reject UNKNOWN and FALSE). The
WHERE clause is applied to the working set in the FROM clause.
c) Go to the optional GROUP BY clause, make groups and reduce each
group to a single row, replacing the original working table with the
new grouped table. The rows of a grouped table must be group
characteristics: (1) a grouping column (2) a statistic about the group
(i.e. aggregate functions) (3) a function or (4) an expression made up
those three items. The original table no longer exists.
d) Go to the optional HAVING clause and apply it against the grouped
working table; if there was no GROUP BY clause, treat the entire table
as one group.
e) Go to the SELECT clause and construct the expressions in the list.
This means that the scalar subqueries, function calls and expressions
in the SELECT are done after all the other clauses are done. The AS
operator can also give names to expressions in the SELECT list. These
new names come into existence all at once, but after the WHERE clause,
GROUP BY clause and HAVING clause have been executed; you cannot use
them in the SELECT list or the WHERE clause for that reason.
If there is a SELECT DISTINCT, then redundant duplicate rows are
removed. For purposes of defining a duplicate row, NULLs are treated
as matching (just like in the GROUP BY).
f) Nested query expressions follow the usual scoping rules you would
expect from a block structured language like C, Pascal, Algol, etc.
Namely, the innermost queries can reference columns and tables in the
queries in which they are contained.
g) The ORDER BY clause is part of a cursor, not a query. The result
set is passed to the cursor, which can only see the names in the SELECT
clause list, and the sorting is done there. The ORDER BY clause cannot
have expression in it, or references to other columns because the
result set has been converted into a sequential file structure and that
is what is being sorted.
As you can see, things happen "all at once" in SQL, not "from left to
right" as they would in a sequential file/procedural language model. In
those languages, these two statements produce different results:
READ (a, b, c) FROM File_X;
READ (c, a, b) FROM File_X;
while these two statements return the same data:
SELECT a, b, c FROM Table_X;
SELECT c, a, b FROM Table_X;
Think about what a mess this statement is in the SQL model.
SELECT f(c2) AS c1, f(c1) AS c2 FROM Foobar;
That is why such nonsense is illegal syntax.