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Why I get exception when I call stored procedure?

I am using Entity Framework 6 and Microsoft SQL Server 2012.
Here is my stored procedure:
ALTER PROCEDURE SPDeleteRegion
#siteId int,
#regionId int
AS
BEGIN
SET NOCOUNT ON;
DECLARE #isDeleted BIT
IF EXISTS (SELECT 1 FROM SiteObjects WHERE SiteRegionId = #regionId)
BEGIN
SET #isDeleted = 0 ; --not deleted
RETURN #isDeleted;
END
ELSE
BEGIN
--do what needs to be done if not
DELETE FROM SiteRegions
WHERE Id = #regionId;
SET #isDeleted = 1; -- deleted
RETURN #isDeleted;
END
END
Here how I call the stored procedure in C#:
var t = _context.Database.SqlQuery<bool>("SPDeleteRegion #siteId, #regionId",
new SqlParameter("#siteId", siteId),
new SqlParameter("#regionId", regionId));
On the line of code above I get this exception:
The data reader has more than one field. Multiple fields are not valid for EDM primitive or enumeration types.
Any idea why I get the excewption and how to fix it?

Your procedure doesn't selecting anything. Change it like this:
ALTER PROCEDURE SPDeleteRegion
-- Add the parameters for the stored procedure here
#siteId int,
#regionId int
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE
#isDeleted BIT
IF EXISTS (SELECT 1 FROM SiteObjects WHERE SiteRegionId = #regionId)
BEGIN
SET #isDeleted = 0 ; --not deleted
SELECT #isDeleted [IsDeleted]; --HERE
END
ELSE
BEGIN
--do what needs to be done if not
DELETE FROM SiteRegions WHERE Id = #regionId;
SET #isDeleted = 1;--deleted
SELECT #isDeleted [IsDeleted]; -- AND HERE
END
END

ADO.NET stored procedure for inserting not working

I have a database which stores information about a library (books, authors & categories).
But I can't get my stored procedure to work for inserting data. The stored procedure itself executes fine, but when I perform a test, it simply doesn't add anything to the database. Can anyone see what I'm missing?
This is my stored procedure (for category):
USE MyLibrary
GO
IF EXISTS (SELECT 1 FROM sysobjects WHERE name = 'CategoryInsert' AND TYPE = 'P')
BEGIN
DROP PROC CategoryInsert
END
GO
CREATE PROCEDURE CategoryInsert
(
#Id int out,
#Name nvarchar(255),
#InsertedBy nvarchar(120),
#InsertedOn datetime
)
AS
DECLARE #CurrentId int
SELECT #CurrentId = Id FROM Category WHERE lower(#Name) = lower(#Name)
IF #CurrentId IS NOT NULL
BEGIN
SET #Id = -100
RETURN
END
INSERT INTO Category
(
Name,
InsertedBy,
InsertedOn
)
VALUES
(
#Name,
#InsertedBy,
#InsertedOn
)
SET #Id = SCOPE_IDENTITY()
GO
This is my test:
USE MyLibrary
GO
DECLARE #NewId int
DECLARE #date datetime
SET #date = getdate()
EXEC CategoryInsert #NewId, 'Testing', 'AL', #date
SELECT #NewId
GO

This line:
SELECT #CurrentId = Id FROM Category WHERE lower(#Name) = lower(#Name)
IF #CurrentId IS NOT NULL
The equality check will always return true because you're essentially comparing WHERE 1 = 1, which means that #CurrentID will always have a value and thus your stored procedure will always return before the INSERT happens.

SQl Transactions - query doesnt return value as expected

tblParent
pid(int) name deleted(bit)
1 abc 0
2 def 0
tblChild
cid(int) name pid(ForeignKey)
1 aaa 1
2 bbb 1
When a record from tblParent is being deleted, it should check for any child records. If yes, rollback & return 0. If no, then update the deleted column to '1' and return 1.
Basically, doing a soft delete
The SP works fine. All I need is to know the status as 0 or 1 based upon the action that took place. How should it be done. I would call this store procedure from c#, linq to entities to get the status.
something like:
public int somefuntion() //returning a string is also fine..
{
return MYDB.SoftDelete(parameters.....);
}
EDIT:
ALTER PROCEDURE SoftDelete
(
#TableName nvarchar(50), #ColName nvarchar(50),
#Id nvarchar(50)
)
AS
BEGIN
DECLARE #qry nvarchar(500)
SELECT #qry = 'begin transaction
delete '+#tablename+' where '+#colname+'='+#id+'
if(##Error <> 0)
Begin
--select 0
End
else
Begin
rollback transaction
update '+#tablename+' set deleted = 1 where '+#colname+' = '+#id+'
--select = 1
end'
EXECUTE sp_executesql #qry
END

Try this:
Declare #status nvarchar(50),#tablename nvarchar(50), #colname nvarchar(50),
#id nvarchar(50), #qry nvarchar(500)
set #tablename = 'person'
set #colname = 'id'
set #id = '15'
begin try
begin transaction
set #qry='delete '+#tablename+' where '+#colname+'=#id'
execute sp_executesql #qry,N'#id nvarchar(50)',#id=#id
rollback
--NO FK violation.So begin another transaction and soft delete
begin transaction
set #qry='update '+#tablename +' set deleted=1 where '+#colname+'=#id'
execute sp_executesql #qry,N'#id nvarchar(50)',#id=#id
commit
select 1
end try
begin catch
print(Error_Message())
--FK violation.Do nothing.Return 0
select 0
end catch

In your script the #status variable is not accessible inside your sql statement you build because "execute sp_executesql #qry" will be executing in different space. Instead use select n" in replace to "set #status = 0" and "set #status = 1"
Try this
Declare #tablename nvarchar(50), #colname nvarchar(50),
#id nvarchar(50), #qry nvarchar(500)
set #tablename = 'tblParent'
set #colname = 'pid'
set #id = '1'
select #qry = 'begin transaction
delete '+#tablename+' where '+#colname+'='+#id+'
if(##Error <> 0)
Begin
select 0
End
else
Begin
rollback transaction
update '+#tablename+' set deleted = 1 where '+#colname+' = '+#id+'
select 1
end
execute sp_executesql #qry

update query returns -1 value eventhough the data is updated in database

update query returns -1 value eventhough the data is updated in database . I am using sql server 2005 stored procedure with c#.
My stored procedure is as follows...
ALTER procedure [dbo].[sp_changepwd]
(
#Cust_Id varchar(50),
#Password varchar(50),
#OldPassword varchar(50),
#Username varchar(50)
)
as
Begin
SET NOCOUNT ON
Begin Tran
update
Customer_Utility_Reg_M_Tbl
set
Password=Convert(varbinary(50),#Password)
where
Cust_Id=#Cust_Id and Password=#OldPassword and Username=#Username
IF ##ERROR = 0
COMMIT TRAN
ELSE
ROLLBACK TRAN
RETURN (##ERROR)
END

SET NOCOUNT OFF when you SET NOCOUNT ON it doesnt report the number of record affected

How to check that a delete / update operation completed successfully when using a stored procedure?

Say we have stored procedure(s) performing simple operations like this:
CREATE PROCEDURE [dbo].[AddNewAuthorReturnID]
(
#Author_Name VARCHAR(MAX),
#Author_ID int OUTPUT
)
AS
SET NOCOUNT OFF;
BEGIN
INSERT INTO AUTHORS (#Author_Name)
VALUES (#Author_Name)
SET #Author_ID = SCOPE_IDENTITY()
SELECT #Author_ID
END
In the above procedure, the returned id is an indication of successful operation.
Consider the equivalent with DELETE.
CREATE PROCEDURE [dbo].[DeleteAuthor]
(
#Author_ID int
)
AS
SET NOCOUNT OFF;
BEGIN
DELETE FROM AUTHORS
WHERE
(Author_ID = #Author_ID)
END
How can we know the operation was
successful and the AUTHORS record was
succesfully removed if we use the above
procedure ?
With an update operation?

You could select ##rowcount
It will show you the rows affected.
e.g
CREATE PROCEDURE [dbo].[DeleteAuthor]
(
#Author_ID int
)
AS
SET NOCOUNT OFF;
BEGIN
DELETE FROM AUTHORS
WHERE
(Author_ID = #Author_ID)
SELECT ##ROWCOUNT
END
This can be applied to update too.
CREATE PROCEDURE [dbo].[UpdateAuthor]
(
#Author_ID int
)
AS
SET NOCOUNT OFF;
BEGIN
UPDATE AUTHORS
SET AuthorName = 'John'
WHERE
(Author_ID = #Author_ID)
SELECT ##ROWCOUNT
END
Alternatively you could use ##Error and raise an error id ##rowcount > 1 (if you only wanted to update one row).
e.g
CREATE PROCEDURE [dbo].[DeleteAuthor]
(
#Author_ID int
)
AS
SET NOCOUNT OFF;
BEGIN
DELETE FROM AUTHORS
WHERE
(Author_ID = #Author_ID)
IF ##ROWCOUNT <>1
BEGIN
RAISERROR ('An error occured',10,1)
RETURN -1
END
END
As Giorgi says this will be returned as a returncode.

You can to return ##ROWCOUNT to determine if your last statement affected any record.

You can return value from stored procedure using return statement. The ##ERROR variable is equal to zero if there was no error.
##ERROR
CREATE PROCEDURE [dbo].[DeleteAuthor]
(
#Author_ID int
)
AS
SET NOCOUNT OFF;
BEGIN
DELETE FROM AUTHORS
WHERE
(Author_ID = #Author_ID)
Return ##ERROR
END