If I have multiple selects like so:
select * from A where A.name = 'linköping'
IF ##ROWCOUNT = 0
begin
select * from A where A.amount = 45
end
...I get 1 result set if the first select returns stuff. But if it runs the second, I get two result sets; the first with no rows and the second with some rows.
Is there a way to only return the second result set if the second select is run ?
I write code like this because of Andrey Gordeev's answer to this post: Can you have if-then-else logic in SQL?
(MSSQL 2000)
Thanks!
You will need to prevent the first select by checking if you will get any results back before running the select.
For example:
IF EXISTS (SELECT 1 FROM A WHERE A.name = 'linköping')
BEGIN
SELECT * FROM A WHERE A.name = 'linköping'
END
ELSE
BEGIN
SELECT * FROM A WHERE A.amount = 45
END
No it is not possible The returning results are depending on number of select statements.
If you want to do the single select follow #RB or #Jwalin Shah solution.
This will work with IF-ELSE Logic. [Tested]
DECLARE #count as int
set #count = (SELECT count(1) from A where A.name = 'linköping')
if (#count = 0)
BEGIN
select * from A where A.amount = 45
END
ELSE
BEGIN
select * from A where A.name = 'linköping'
END
Try this
IF ##ROWCOUNT = 0
BEGIN
select * from A where A.amount = 45
END
ELSE
BEGIN
select * from A where A.name = 'linköping'
END
Related
I have the following simplified stored procedure where based on on the input parameter, I need to then do a case in the where clause. It will not execute as it says: Incorrect syntax near '='
PROCEDURE [dbo].[DataInfo]
#Allowactive BIT = 1
AS
BEGIN
Select * from tbl1 1
where (CASE #Allowactive
WHEN 0 then (t.Isactive = 1) END
AND isSubmitted = 1
END
your where clause will be like below
where
CASE #Allowactive
WHEN 0 then t.Isactive END =1
AND isSubmitted = 1
You shouldn't use parameters in a query like this, as it messes up the query plan. When the right plan to use changes depending on the parameter, you need separate queries, or to force SQL to always recompile.
So do this instead:
create or alter procedure [dbo].[DataInfo] #Allowactive bit = 1
as
begin
if #Allowactive = 0
begin
Select * from tbl1 1
where Isactive = 1
AND isSubmitted = 1
end
else
begin
select * from tbl1 1
where isSubmitted = 1
end
end
Instead run separate queries.
Try to run the following and see the results:
SELECT *
FROM Tbl1 AS T
WHERE CASE #Allowactive
WHEN 0 THEN 1 ELSE #Allowactive END = T.Isactive
AND
isSubmitted = 1;
If you have 2012+ version then you could also do:
SELECT *
FROM Tbl1 AS T
WHERE IIF(#Allowactive = 0, 1, #Allowactive) = T.Isactive;
It seems Zaynul Abadin Tuhin directly answers your question.
But, I believe a case statement complicates what you want to achieve.
I think a query like this satisfies your desired outcome:
PROCEDURE [dbo].[DataInfo]
#Allowactive BIT = 1
AS
BEGIN
SELECT * FROM tbl1 t
WHERE (#Allowactive = 1 OR (#Allowactive = 0 AND t.Isactive = 1))
AND t.isSubmitted = 1
END
I have a condition which based on my Count result, it should skip or include a join in my query,to make short the story,how to implement such a thing in SQL:
select count(names) as rslt
if(rslt)>0 then
select......join tables
else
Select...
as you see I want to say if the count is >0 then do the join otherwise it should skip then join and go to the next line,how should I achieve this?
DECLARE #Name INT
SELECT
#Name = COUNT(names)
FROM Table
IF #Name > 0
BEGIN
PRINT 'Do somthing'
END
ELSE
PRINT 'Do something else'
END
Just change the PRINT statements to your query logic
If you want to check if a resulting query returns any row (>0) then you should use an IF with an EXISTS rather than using COUNT. EXISTS will make the SQL engine stop running once it finds at least 1 row, while COUNT will force to actually count all records.
IF EXISTS (SELECT 1 FROM YourTable WHERE names IS NOT NULL)
BEGIN
SELECT
YourColumn
FROM
Table1
INNER JOIN Table2 ON --...
END
ELSE
BEGIN
SELECT
YourColumn
FROM
Table1
END
If on the other hand you need to check a specific amount, then you will have to COUNT and assign to variable.
DECLARE #CountTotal INT = (SELECT COUNT(names) FROM YourTable)
IF #CountTotal > 100
BEGIN
SELECT
YourColumn
FROM
Table1
INNER JOIN Table2 ON --...
END
ELSE
BEGIN
SELECT
YourColumn
FROM
Table1
END
DECLARE #reslt integer
#reslt = select count(names)
if #reslt >0 then
select......join tables
You need to put it in a variable and then call it.
You can also use dynamic query like below:
DECLARE #SQL NVARCHAR(MAX);
SELECT #SQL = N'SELECT *
FROM T1 ' + CASE WHEN (SELECT COUNT(names) FROM table1) > 0 THEN +
' INNER JOIN T2 ON T1.Id = T2.Id ' ELSE '' END
PRINT #SQL
EXEC sp_executesql #SQL;
Use CASE function, something like this :
Select count(CustomerID),
CASE
WHEN count(CustomerID) > 30 THEN "The quantity is greater than 30"
WHEN count(CustomerID) = 30 THEN "The quantity is 30"
ELSE "The quantity is something else"
END
FROM Customers;
You Can try below method as well.
if((select count(Name) from tableName)>0)
begin
select 1
end
else
begin
select 2
end
No need to use one temp variable to store the count .
I need to get the output of a selected query depending on certain conditions
Means if(id=uid)
then I need the below query
select * from table1 where id=5;
else
I need the below one
select * from table1 where id=10
I know i can use if condition for this. But my query is very long one so when I use if else then it would look like
if(#id=#uid)
begin
select * from table1 where id=5;// query 1
end
else
select * from table1 where id=10;//query 2
but here I need to replace the entire query once again for a single check. I hope I can do something like this:
declare #id int=4;
declare #uid=10;
select * from table1 where
case
when #id=#uid
then
id=5
else
id=10;
end
Updation
I need one more condition too
in this case id=5 and uid=10
then if(id=uid)
then
select * from table1 where id=5
and
if(id!=uid)
then
select * from table1
something like this
You can use the case expression to return the value id should be equal to:
SELECT *
FROM table1
WHERE id = CASE WHEN #id = #uid THEN 5 ELSE 10 END;
EDIT:
The updated requirement in the question is to return all rows when #id != #uid. This can be done by comparing id to id:
SELECT *
FROM table1
WHERE id = CASE WHEN #id = #uid THEN 5 ELSE id END;
Alternatively, with this updated requirement, a simple or expression might be simpler to use:
SELECT *
FROM table1
WHERE #id = #uid OR id = 5;
SELECT * FROM table1
WHERE (id=5 AND #id=#uid) OR (id=10 AND #id<>#uid)
SELECT
*
FROM
table1
WHERE
(
#id = #uid
AND
id =5
)
OR
(
not #id = #uid
AND
id=10
)
I have a stored procedure that I would like to query either the production or the "work in progress" table, based on the parameter I am passing in. I could write two separate stored procedures, but I thought this was worth a try.
something along the lines of:
create procedure getUserDetails
#userID int,
#prod varchar(5)
as
begin
select * from
if (#prod = 'true')
Begin
userprod_table
else
userwip_table
end
where something = 'something'
END
Is this at all possible? I wouldn't want to write 2 SP that are almost identical :-/
Why not use a simple if(#prod = 'true') statement like below:
if (#prod = 'true')
begin
select * from userprod_table where something = 'something'
end else
begin
select * from userwip_table where something = 'something'
end
You could use a CTE so that your main query isn't repeated
with usertable as
(
select * from userprod_table where 1 = #flag
union
select * from userwip_table where 0 = #flag
)
select ... from usertable ...
I'm trying to solve the following problem:
I would like to make a select, when the result is empty it should be replaced with 'empty' Else all lines of the result should be there.
Like:
if (select has no result)
{
One Line as result with 'no result'
}
else
{
post every line of the select result
}
That is my try:
select case when count(*) = 0
then 'no Entry'
else Members --all Members should be here
END as Member
from tableMember where Membergroup = 'testgroup';
Thanks to everybody who can help me!
PLEASE show me the COMPLETE code that is needed to use the query in Oracle
Try this:
DECLARE #counter int
SET #counter = (select count(*) from tableMember where Membergroup = 'testgroup');
IF (#counter > 0)
BEGIN
SELECT * FROM Members
END
ELSE
BEGIN
SELECT 'No results!'
END
Regards
FOR ORACLE
DECLARE C INTEGER;
SELECT COUNT(*) INTO C FROM tableMember WHERE Membergroup = 'testgroup';
IF C > 0
THEN
SELECT * FROM tableMember;
ELSE
SELECT 'No results!' FROM tableMember;
END IF;
MS-SQL ONLY
IF EXISTS(SELECT * FROM tableMember WHERE Membergroup = 'testgroup')
BEGIN
SELECT * FROM tableMember
END
ELSE
BEGIN
SELECT 'No results!'
END
I would rather do this in the application code rather than stored procedures. What you are trying to do here is user experience related work which IMHO is something database should not care about.