query with user-define function

I have a table with 3 fields.
In the first field named a there are values i.e. 5
In the second field named b there are values i.e. 9
In the third field named c there are expressions i.e. a+3*b (where a,b
supposed to be the contents of the previous fields).
How can I issue a query to get back 5, 9, 32 (5+3*9)'
Many Thanks
HelenNot sure why you want to do this in SQL. Note that if dbo.foo has more than
one row, you will need to limit both queries using a WHERE clause to
identify that single row (unless the expression in c is always the same, in
which case, it shouldn't be in the table at all).
CREATE TABLE dbo.foo
(
a INT,
b INT,
c VARCHAR(32)
)
GO
SET NOCOUNT ON
GO
INSERT dbo.foo SELECT 5,9,'a+3*b'
GO
DECLARE @.sql VARCHAR(255)
SELECT @.sql = 'SELECT a,b,'+c+' FROM dbo.foo'
FROM dbo.foo
EXEC(@.sql)
GO
DROP TABLE dbo.foo
GO
"Helen" <Helen@.discussions.microsoft.com> wrote in message
news:092F2AF9-CF18-4D28-9112-E4D9D459BE79@.microsoft.com...
>I have a table with 3 fields.
> In the first field named a there are values i.e. 5
> In the second field named b there are values i.e. 9
> In the third field named c there are expressions i.e. a+3*b (where a,b
> supposed to be the contents of the previous fields).
> How can I issue a query to get back 5, 9, 32 (5+3*9)'
> Many Thanks
> Helen|||Hi,
You can have 3 solutions
1. Direct TSQL . Select a,b,(a+3*b) as c from table_name
2. Create a view. Create view v1 as Select a,b,(a+3*b) as c from table_name
and later use
select * v1
3. Use compute columns while table creation
create table cc(a int, b int, c AS (a + 3 * b))
WHILE INSERTION INSERT DATA ONLY FORM COLUMN a AND b
Thanks
Hari
SQL Server MVP
"Helen" <Helen@.discussions.microsoft.com> wrote in message
news:092F2AF9-CF18-4D28-9112-E4D9D459BE79@.microsoft.com...
>I have a table with 3 fields.
> In the first field named a there are values i.e. 5
> In the second field named b there are values i.e. 9
> In the third field named c there are expressions i.e. a+3*b (where a,b
> supposed to be the contents of the previous fields).
> How can I issue a query to get back 5, 9, 32 (5+3*9)'
> Many Thanks
> Helen

Query with user-define function

I have a table with 3 fields. In the first field named a there are values
i.e. 5
In the second field named b there are values i.e. 9
In the third field named c there are expressions i.e. a+@.q+3*b where a,b
supposed to be the contents of the previous fields, different in each row
and @.q is a variable I wound like to type each time I run the query.
I have typed:
DECLARE @.sql VARCHAR(255)
SELECT @.sql = 'SELECT a,b' + c+ ' FROM dbo.foo where Index=1 '
FROM dbo.foo where Index=1
EXEC(@.sql)
How can I write a query where @.q=7 to get back 5, 9, 39 (5+7+3*9)'
Many Thanks
HelenDECLARE @.q INT
SET @.q = 7
SELECT a,b, a + @.q + 3 *b AS c
FROM dbo.foo
where Index=1
Jacco Schalkwijk
SQL Server MVP
"Helen" <Helen@.discussions.microsoft.com> wrote in message
news:A3A0BB12-2B9D-4173-81B3-F17D30F6D59B@.microsoft.com...
>I have a table with 3 fields. In the first field named a there are values
> i.e. 5
> In the second field named b there are values i.e. 9
> In the third field named c there are expressions i.e. a+@.q+3*b where a,b
> supposed to be the contents of the previous fields, different in each row
> and @.q is a variable I wound like to type each time I run the query.
> I have typed:
> DECLARE @.sql VARCHAR(255)
> SELECT @.sql = 'SELECT a,b' + c+ ' FROM dbo.foo where Index=1 '
> FROM dbo.foo where Index=1
> EXEC(@.sql)
> How can I write a query where @.q=7 to get back 5, 9, 39 (5+7+3*9)'
> Many Thanks
> Helen
>|||I'm sorry. I didn't explain myself correctly. I mean I have this table in a
SQL Server with many rows and different function in each row. Inside the
function I would like to have a variable (@.q) which I don't know how to writ
e
so as when I query I can put a different value each time.

> "Helen" <Helen@.discussions.microsoft.com> wrote in message
> news:A3A0BB12-2B9D-4173-81B3-F17D30F6D59B@.microsoft.com...
>
>|||Hi
Maybe
CREATE TABLE foo ( [index] int not null identity(1,1), a int, b int, c
varchar(10) )
INSERT INTO Foo ( a, b, c ) SELECT 5,9,'a+@.q+3*b'
DECLARE @.sql VARCHAR(255)
SELECT @.sql = 'DECLARE @.q int SET @.q=7 SELECT a,b,' + c+ ' FROM dbo.foo
where [Index]=1'
FROM dbo.foo where [Index]=1
EXEC(@.sql)
John
"Helen" <Helen@.discussions.microsoft.com> wrote in message
news:A3A0BB12-2B9D-4173-81B3-F17D30F6D59B@.microsoft.com...
>I have a table with 3 fields. In the first field named a there are values
> i.e. 5
> In the second field named b there are values i.e. 9
> In the third field named c there are expressions i.e. a+@.q+3*b where a,b
> supposed to be the contents of the previous fields, different in each row
> and @.q is a variable I wound like to type each time I run the query.
> I have typed:
> DECLARE @.sql VARCHAR(255)
> SELECT @.sql = 'SELECT a,b' + c+ ' FROM dbo.foo where Index=1 '
> FROM dbo.foo where Index=1
> EXEC(@.sql)
> How can I write a query where @.q=7 to get back 5, 9, 39 (5+7+3*9)'
> Many Thanks
> Helen
>|||Helen,
The T-SQL infix expression evaluator here might help:
http://users.drew.edu/skass/SQL/Infix.sql.txt
If you first replace the 'a', 'b', and @.q in your expression
with their values, InFixVal should then evaluate the result.
select
a, b,
dbo. InFixVal(replace(replace(replace(c,'a','
('+str(a,19,4)+')'),'b','('+str(
b,19,4)+')'),'@.q,str(@.q,19,4)),1)
from ...
Also look here, for some examples of its use, and comments
about its limitations. It only evaluates a simple set of possible
arithmetic expressions, but it may be enough for you.
http://groups.google.com/groups?hl=...ver&qt_s=Search
Steve Kass
Drew University
"Helen" <Helen@.discussions.microsoft.com> wrote in message
news:A3A0BB12-2B9D-4173-81B3-F17D30F6D59B@.microsoft.com...
>I have a table with 3 fields. In the first field named a there are values
> i.e. 5
> In the second field named b there are values i.e. 9
> In the third field named c there are expressions i.e. a+@.q+3*b where a,b
> supposed to be the contents of the previous fields, different in each row
> and @.q is a variable I wound like to type each time I run the query.
> I have typed:
> DECLARE @.sql VARCHAR(255)
> SELECT @.sql = 'SELECT a,b' + c+ ' FROM dbo.foo where Index=1 '
> FROM dbo.foo where Index=1
> EXEC(@.sql)
> How can I write a query where @.q=7 to get back 5, 9, 39 (5+7+3*9)'
> Many Thanks
> Helen
>sql