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One way is to use inline views, like:
SELECT alias1.Result
FROM (SELECT (ColA - ColB) AS Result
FROM Table) alias1
WHERE alias1.result > 0
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Thanks for the reply. I was just kind of hoping there was a way to store the value in a temp variable on a row by row basis, but using inline views does the trick as well - so thanks.
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toticow wrote: I was just kind of hoping there was a way to store the value in a temp variable on a row by row basis
That won't be possible (and wouldn't be efficient) since sql is set based language. What you were hoping for would be record based and this would be close to cursor handling (and of course could be implemented in an procedure using cursors). But you don't want to use cursors since (as Mycroft in this forum said) they are evil
Also have a look at other set based variations Ben Fair posted.
toticow wrote: so thanks
You're welcome.
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In SQL Server 2005+ you can use CTEs (Common Table Expressions) to do the same kind of thing:
WITH Results AS
(
SELECT ColA - ColB [Result]
FROM TABLE
)
SELECT *
FROM Results
WHERE Result > 0
Or with a temp table like so:
SELECT ColA - ColB [Result]
INTO #temp
FROM TABLE
SELECT *
FROM #temp
WHERE Result > 0
DROP TABLE #temp
Or with a table variable like so:
DECLARE @temp TABLE (Result int)
INSERT @temp
SELECT ColA - ColB [Result]
FROM TABLE
SELECT *
FROM @temp
WHERE Result > 0
I prefer to use the CTE because I think it's less code and easily readable.
Keep It Simple Stupid! (KISS)
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That's true and leads to the same result. Writing inlines is just a (bad) habit that always comes first in mind. Guess it's because I've written them over fifteen years so I believe it's like teaching an old dog...
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Well, I can relate to that!
Keep It Simple Stupid! (KISS)
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Mika Wendelius wrote: comes first in mind
Probably more portable too?
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PIEBALDconsult wrote: Probably more portable too?
I'd say so. Many DBMS support inline views.
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In Oracle 9i the maximum length of a list used in an IN clause is 1000 records.
Does anyone know if it's still the same limit in version 10g or 11g?
A related question is what the limit is in SQLServer?
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Jörgen Andersson wrote: In Oracle 9i the maximum length of a list used in an IN clause is 1000 records
In Oracle 1000 limitation is not for records, but only for comma separated values in the list. So you cannot pass more literal values for an IN-list than 1000.
Jörgen Andersson wrote: Does anyone know if it's still the same limit in version 10g or 11g?
At least in 10g this applies.
Jörgen Andersson wrote: A related question is what the limit is in SQLServer
In SQL Server I'm not aware of such limitation. The limitation you could hit is the maximum size of a sql statement which is 65,536 * network packet size.
Mika
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Thanks!
Mika Wendelius wrote: In Oracle 1000 limitation is not for records, but only for comma separated values in the list. So you cannot pass more literal values for an IN-list than 1000
I know, I'll try to express myself better in the future.
Mika Wendelius wrote: At least in 10g this applies
Which means I'll have to keep on using temp tables.
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Jörgen Andersson wrote: Thanks!
You're welcome
Jörgen Andersson wrote: Which means I'll have to keep on using temp tables
That's one possibility, but since the the values for IN come from a subquery, you can use basically all the techniques what the database offers to create the result set (normal tables, temporary tables, xml tables, external tables etc etc).
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Mika Wendelius wrote: hat's one possibility, but since the the values for IN come from a subquery, you can use basically all the techniques what the database offers to create the result set (normal tables, temporary tables, xml tables, external tables etc etc).
The data for the IN clause (or maybe rather a join) is coming from a .net datatable.
Is there an easier way than inserting it into a temptable?
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Since I don't know the wholse situation, just throwing some ideas:
- Can you put the data into an xml format and in the subquery use xquery to fetch the data again
- if you're inserting data into the database using this IN operator, you could use arrays to pass the data to a procedure
- if you're selecting data you can do the same and then return ref cursor
- possibly you could use UDT's in the above scenarios
- you could create a function as pipelined, pass the data to that with an array and then use the return value of the function as a table in your subquery etc.
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Thanks again.
I'll have a deeper look into this tomorrow. Eventually with another question...
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hi
i have a update trigger that get fired when any column updated of the table
create TRIGGER trigger_Update_ABC
ON ABC
FOR Update
AS
declare @Id bigint
set @Id = (select Id from Inserted)
update ABC set ABC.Post = getdate() where Id =@Id
when i execute such sql quarry
Update ABC set ABC.Active = 1 where ABC.Id in(1,4,5,6,3,7)
then i got error
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Triggers must *always* be written with the expectation that multiple rows will be affected. So SELECT ID from Inserted could return a series of INT not just one.
CREATETRIGGER trigger_Update_ABC ON ABC
FOR Update AS
UPDATE ABC
SET ABC.Post = GetDate()
WHERE ABC.ID IN (SELECT ID from inserted)
You should check to see if recursive triggers are set on your server, as this is an update trigger on ABC that updates ABC. If recursive triggers are enabled it could cause an infinite loop and the statement will fail.
Do some research into recursive triggers if this is enabled.
'Howard
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than x Richards
my confusion is now much clear now
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Full-text index tab is disabled and
I can only see partition schemes and partition functions under storage.
Help me out in this regard.
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i got a procedure in SQL Server at the end of the program i write this code
SELECT @@IDENTITY
COMMIT TRANSACTION INSERT_NOMENCLATURE
RETURN
the problem that i don't have the column name of SELECT @@IDENTITY how can i manage it to get the value with a column name
thanks!
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papy-boom wrote: i don't have the column name of SELECT @@IDENTITY how can i manage it to get the value with a column name
You don't know from which column @@IDENTITY returns the value. It just returns the last inserted identity value in your sesion. It can be any table and any identity column.
You can narrow the possibilities using SCOPE_IDENTITY, but you'd still face the same problem.
Normally you know where @@IDENTITY comes from in your procedure since it's the previous insert to identity columned table. What's the cause in your case that prevents you identifying the statement (and after that the table and the column)?
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you mean if i replaced by select max from my table it will works?
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papy-boom wrote: you mean if i replaced by select max from my table it will works?
No, that's not what I mean.
Since you didn't post any code or any explanation why do you want to know the column name, I can't say what's the answer for you.
Consider that I have a table:
CREATE TABLE Artist (
[Artist#] int NOT NULL IDENTITY(1,1) PRIMARY KEY,
[Name] nvarchar(100) NOT NULL
);
Then when I'm executing this piece of statement:
INSERT INTO Artist ([Name]) VALUES (@name);
SET @artistIdentity= @@IDENTITY;
Now on the 2'nd line I know that @@IDENTITY returns a value that is assigned to Artist# column in Artist table since that's the previous INSERT statement to a table that has an identity column.
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the problem that is that in code part i have a datareader to read the value returned value and the argument to pass to datareader is the name of the column so if my procedure return me a value without the name of column it's not simple to get the value so i tried to get select @@IDENTITY AS returnedvalue to get the name of column but it doesn't work
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