When I try to run the following statement, I get this error:
"A SELECT statement that assigns a value to a variable must not be combined with data-retrieval operations."
DECLARE #OFR DECIMAL(18,2)
;
SELECT #OFR =
CASE SUM(ofr.Quantity)
WHEN 0 THEN 0
ELSE SUM(ofr.Gross) / SUM(ofr.Quantity)
END
FROM DistributionCosts ofr
;
SELECT #OFR
I just want to stick the result of that case statement into a variable and I'm getting stuck here.
Any ideas?
Thanks.
Are you sure this is where your error is? I just ran the statement below and it worked:
DECLARE #OFR DECIMAL(18,2)
;
with DistributionCosts as
(
select 1 as quantity, 5 as gross
union
select 5 , 20
)
SELECT #OFR =
CASE SUM(ofr.Quantity)
WHEN 0 THEN 0
ELSE SUM(ofr.Gross) / SUM(ofr.Quantity)
END
FROM DistributionCosts ofr
;
SELECT #OFR
If I select a column in addition to setting a variable I do get your error... If you are selecting another column you will need to either stop selecting that column or assign that column to a local variable as well.
Related
I developed the following function:
create function kv_fn_ValuationPerItem_AW (#dDate date, #active bit)
returns table
as
return
(
select
Code ItemCode
, Description_1 ItemDescription
, ItemGroup
, Qty_On_Hand CurrentQtyOnHand
, AveUCst CurrentAvgCost
, Qty_On_Hand*AveUCst CurrentValue
from _bvSTTransactionsFull t
inner join StkItem s on t.AccountLink = s.StockLink
where ServiceItem = 0
and ItemActive = #active
and TxDate <= #dDate
group by Code, Description_1, ItemGroup, Qty_On_Hand, AveUCst
)
The function requires two parameters:
Date
Is the item Active - 1 = Active & 0 = Inactive
If I use the function as stipulated above, by specifying 1 for the Active Parameter, then the results will only be for Active Items.
If I specify 0, then it'll return all inactive Items.
How do I alter this function to cater for Active Items or both Active & Inactive?
i.e. if the parameter is 1, the where clause should read as ItemActive = #active, but when it's 0, the where clause should read as ItemActive in (1,0), How do I change the function to work like this?
I tried a case, but my syntax is not correct...
It's as simple as adding an or to your where cluase:
...
and (ItemActive = 1 OR #active = 0)
...
BTW, you might want to do it like this instead:
and (ItemActive = #active OR #active IS NULL)
which means that when you pass in 1 as #active you'll get only the active items, when you pass in 0 you'll get only the inactive members, but when you pass in null you'll get all records, regardless of the value in the ItemActive column.
Thanks Shnugo & Zohar for your answers,
Please amend your answers, then I'll mark yours as the answer.
The solution to my problem was to alter the Function as following:
create function kv_fn_ValuationPerItem_AW (#dDate date, #active bit)
returns table
as
return
(
select
Code ItemCode
, Description_1 ItemDescription
, ItemGroup
, Qty_On_Hand CurrentQtyOnHand
, AveUCst CurrentAvgCost
, Qty_On_Hand*AveUCst CurrentValue
from _bvSTTransactionsFull t
inner join StkItem s on t.AccountLink = s.StockLink
where ServiceItem = 0
and ItemActive in (1,#active)
and TxDate <= #dDate
group by Code, Description_1, ItemGroup, Qty_On_Hand, AveUCst
)
I think you are looking for this:
DECLARE #mockup TABLE(ID INT IDENTITY,SomeValue VARCHAR(100),Active BIT);
INSERT INTO #mockup VALUES('Row 1 is active',1)
,('Row 2 is active',1)
,('Row 3 is inactive',0)
,('Row 4 is inactive',0);
DECLARE #OnlyActive BIT=0; --set this to 1 to see active rows only
SELECT *
FROM #mockup m
WHERE (#OnlyActive=0 OR m.Active=1);
The idea is: If the parameter is set to 0 this expression is always true, if not, the column Active must be set to 1.
Hint: I used paranthesis, which was not needed in this simple case. But in your more complex WHERE clause they will be needed...
Hint2: I named the parameter OnlyActive, which expresses a bit better what you are looking for. You might turn the parameter to ShowAll with an invers logic too...
I have written a cursor to search through a table looking at one bit value.
If all values are 1, I send an email. But if one value is 0 in any row, I don't send the email. The issue that I am having comes in my If statement. In SSMS, "#isComplete = 0" is breaking with only an "Incorrect syntax" error. I am not sure what I am missing here. My code is below. Thank you.
-------------------------------------------------
-- Start the INNER Cursor --
-------------------------------------------------
DECLARE #Complete int
DECLARE #isComplete Bit = 1
DECLARE INNERCur CURSOR FOR
SELECT Complete
FROM #AAEAPVS
OPEN INNERCur
FETCH NEXT FROM INNERCur INTO #Complete
WHILE ##FETCH_STATUS = 0
BEGIN
If #Complete = 0
BEGIN
#isComplete = 0
END
FETCH NEXT FROM INNERCur INTO #Complete
END
CLOSE InnerCurs
DEALLOCATE InnerCurs
-------------------------------------------------
-- INNER Curser END --
-------------------------------------------------
The incorrect syntax is that you need to use SET to assign the variable value, so change
#isComplete = 0
to
SET #isComplete = 0
And assuming you want to exit as soon as you find something that is not complete you should change your WHILE condition to
WHILE ##FETCH_STATUS = 0 AND #isComplete = 1
But most important of all, you probably don't need to use a cursor at all - you should avoid cursors in SQL if possible. You can probably just do something like this
DECLARE #isComplete Bit = 1
IF EXISTS (SELECT * FROM #AAEAPVS WHERE Complete = 0)
BEGIN
SET #isComplete = 0
END
and even that is more than you need, you can do it in a single statement
DECLARE #isComplete Bit = 1
SELECT #isComplete = 0 FROM #AAEAPVS WHERE Complete = 0
The syntax error results from not having a statement on the line. You need to use either SET or SELECT to assign a value to a variable, e.g. set #isComplete = 0.
Why, pray tell, a cursor rather than a simple EXISTS query? A far more efficient solution is:
select #isComplete = case
when exists ( select 42 from #AAEAPVS where Complete = 0 ) then 0
else 1 end;
Tip: It is helpful to tag database questions with both the appropriate software (MySQL, Oracle, DB2, ...) and version, e.g. sql-server-2014. Differences in syntax and features often affect the answers.
Can anyone tell me how to translate the following T-SQL statement:
SELECT fileld1 = CASE
WHEN T.option1 THEN -1
ELSE
CASE WHEN T.option2 THEN 0
ELSE 1
END
END
FROM Table1 AS T
The point is I need to validate two different options from the table for a single field in the select statement..
I have tried to do somthing with an IF statement in pl/sql, but it just doesnt work for me:
SELECT IF T.option1 THEN -1
ELSE IF T.option2 THEN 0
ELSE 1
END
FROM Table1 AS T
I am not actually sure how to write IF statement inside the SELECT statement..
And also, I need to do it INSIDE the select statement because I am constructing a view.
Use:
SELECT CASE
WHEN T.option1 = ? THEN -1
WHEN T.option2 = ? THEN 0
ELSE 1
END AS field1
FROM Table1 AS T
I can't get your original TSQL to work - I get:
Msg 4145, Level 15, State 1, Line 4
An expression of non-boolean type specified in a context where a condition is expected, near 'THEN'.
...because there's no value evaluation. If you're checking if the columns are null, you'll need to use:
SELECT CASE
WHEN T.option1 IS NULL THEN -1
WHEN T.option2 IS NULL THEN 0
ELSE 1
END AS field1
FROM Table1 AS T
...or if you need when they are not null:
SELECT CASE
WHEN T.option1 IS NOT NULL THEN -1
WHEN T.option2 IS NOT NULL THEN 0
ELSE 1
END AS field1
FROM Table1 AS T
CASE expressions shortcircuit - if the first WHEN matches, it returns the value & exits handling for that row - so the options afterwards aren't considered.
If I remember correctly, PL/SQL also supports the case. You just would have to move the column alias from "field1=" before the expression to "AS filed1" after the expression.
I have a huge query which uses case/when often. Now I have this SQL here, which does not work.
(select case when xyz.something = 1
then
'SOMETEXT'
else
(select case when xyz.somethingelse = 1)
then
'SOMEOTHERTEXT'
end)
(select case when xyz.somethingelseagain = 2)
then
'SOMEOTHERTEXTGOESHERE'
end)
end) [ColumnName],
Whats causing trouble is xyz.somethingelseagain = 2, it says it could not bind that expression. xyz is some alias for a table which is joined further down in the query. Whats wrong here? Removing one of the 2 case/whens corrects that, but I need both of them, probably even more cases.
SELECT
CASE
WHEN xyz.something = 1 THEN 'SOMETEXT'
WHEN xyz.somethingelse = 1 THEN 'SOMEOTHERTEXT'
WHEN xyz.somethingelseagain = 2 THEN 'SOMEOTHERTEXTGOESHERE'
ELSE 'SOMETHING UNKNOWN'
END AS ColumnName;
As soon as a WHEN statement is true the break is implicit.
You will have to concider which WHEN Expression is the most likely to happen. If you put that WHEN at the end of a long list of WHEN statements, your sql is likely to be slower. So put it up front as the first.
More information here: break in case statement in T-SQL
declare #n int = 7,
#m int = 3;
select
case
when #n = 1 then
'SOMETEXT'
else
case
when #m = 1 then
'SOMEOTHERTEXT'
when #m = 2 then
'SOMEOTHERTEXTGOESHERE'
end
end as col1
-- n=1 => returns SOMETEXT regardless of #m
-- n=2 and m=1 => returns SOMEOTHERTEXT
-- n=2 and m=2 => returns SOMEOTHERTEXTGOESHERE
-- n=2 and m>2 => returns null (no else defined for inner case)
If logical test is against a single column then you could use something like
USE AdventureWorks2012;
GO
SELECT ProductNumber, Category =
CASE ProductLine
WHEN 'R' THEN 'Road'
WHEN 'M' THEN 'Mountain'
WHEN 'T' THEN 'Touring'
WHEN 'S' THEN 'Other sale items'
ELSE 'Not for sale'
END,
Name
FROM Production.Product
ORDER BY ProductNumber;
GO
More information - https://learn.microsoft.com/en-us/sql/t-sql/language-elements/case-transact-sql?view=sql-server-2017
OK, the umpteenth conditional column question:
I'm writing a stored proc that takes an input parameter that's mapped to one of several flag columns. What's the best way to filter on the requested column? I'm currently on SQL2000, but about to move to SQL2008, so I'll take a contemporary solution if one's available.
The table queried in the sproc looks like
ID ... fooFlag barFlag bazFlag quuxFlag
-- ------- ------- ------- --------
01 1 0 0 1
02 0 1 0 0
03 0 0 1 1
04 1 0 0 0
and I want to do something like
select ID, name, description, ...
from myTable
where (colname like #flag + 'Flag') = 1
so if I call the sproc like exec uspMyProc #flag = 'foo' I'd get back rows 1 and 4.
I know I can't do the part in parens directly in SQL. In order to do dynamic SQL, I'll have to stuff the entire query into a string, concatenate the #flag param in the WHERE clause and then exec the string. Aside from the dirty feeling I get when doing dynamic SQL, my query is fairly large (I'm selecting a couple dozen fields, joining 5 tables, calling a couple of functions), so it's a big giant string all because of a single line in a 3-line WHERE filter.
Alternately, I could have 4 copies of the query and select among them in a CASE statement. This leaves the SQL code directly executable (and subject to syntax hilighting, etc.) but at the cost of repeating big chunks of code, since I can't use the CASE on just the WHERE clause.
Are there any other options? Any tricky joins or logical operations that can be applied? Or should I just get over it and exec the dynamic SQL?
There are a few ways to do this:
You can do this with a case statement.
select ID, name, description, ...
from myTable
where CASE
WHEN #flag = 'foo' then fooFlag
WHEN #flag = 'bar' then barFlag
END = 1
You can use IF.
IF (#flag = 'foo') BEGIN
select ID, name, description, ...
from myTable
where fooFlag = 1
END ELSE IF (#flag = 'bar') BEGIN
select ID, name, description, ...
from myTable
where barFlag = 1
END
....
You can have a complicated where clause with a lot of parentheses.
select ID, name, description, ...
from myTable
where (#flag = 'foo' and fooFlag = 1)
OR (#flag = 'bar' and barFlag = 1) OR ...
You can do this with dynamic sql:
DECLARE #SQL nvarchar(4000)
SELECT #SQL = N'select ID, name, description, ...
from myTable
where (colname like ''' + #flag + 'Flag'') = 1'
EXECUTE sp_ExecuteSQL #SQL, N''
There are more, but I think one of these will get you going.
"Alternately, I could have 4 copies of the query and select among them in a CASE statement."
You don't need to copy your entire query 4 times, just add all the possibilities into the where clauses in your single copy of the query:
select ID, name, description, ...
from myTable
where (#flag = 'foo' and fooFlag = 1) OR (#flag = 'bar' and barFlag = 1) OR ...
What I would do is CASE some variables at the beginning. Example:
DECLARE
#fooFlag int,
#barFlag int,
#bazFlag int,
#quuxFlag int
SET #fooFlag = CASE WHEN #flag = 'foo' THEN 1 ELSE NULL END
SET #barFlag = CASE WHEN #flag = 'bar' THEN 1 ELSE NULL END
SET #bazFlag = CASE WHEN #flag = 'baz' THEN 1 ELSE NULL END
SET #quuxFlag = CASE WHEN #flag = 'quux' THEN 1 ELSE NULL END
SELECT ID, name, description, ...
FROM myTable
WHERE (fooFlag >= ISNULL(#fooFlag, 0) AND fooFlag <= ISNULL(#fooFlag, 1))
AND (barFlag >= ISNULL(#barFlag, 0) AND barFlag <= ISNULL(#barFlag, 1))
AND (bazFlag >= ISNULL(#bazFlag, 0) AND bazFlag <= ISNULL(#bazFlag, 1))
AND (quuxFlag >= ISNULL(#quuxFlag, 0) AND quuxFlag <= ISNULL(#quuxFlag, 1))
The good thing about this query is that, because the possible values for "flags" are bounded, you can calculate all your conditionals as prerequisites instead of wrapping columns in them. This guarantees a high-performance index seek on whichever columns are indexed, and doesn't require writing any dynamic SQL. And it's better than writing 4 separate queries for obvious reasons.
You could have a parameter for each possible flag column, then check if the parameter is null or the value in the column is equal to the parameter. Then you pass in a 1 for the flags that you want to check and leave the others null.
select id, name, description, ...
from myTable
where (#fooFlag is null or fooFlag = #fooFlag) AND
(#barFlag is null or barFlag = #barFlag) AND
...
Honestly, though, this seems like an ideal candidate for building a dynamic LINQ query and skipping the SPROC once you get to SQL2008.
int should be accepted as varchar value
declare #CompanyID as varchar(10) = '' -- or anyother value
select * from EmployeeChatTbl chat
where chat.ConversationDetails like '%'+#searchKey+'%'
and
(
(0 = CASE WHEN (#CompanyID = '' ) THEN 0 ELSE 1 END)
or
(chat.CompanyID = #CompanyID)
)
working
when the companyID is present , then filtration based on it is done, other wise , filtration is skipped.
where
case when #value<>0 then Field else 1 end
=
case when #value<>0 then #value else 1 end