Subquery returns more than one value? - sql

Question

I'm trying to use a stored procedure I wrote that is supposed to create a new project in a "Project" table. It also checks to see if there is a saved project in a "Saved Project" table with the same ID and deletes it upon successful creation.
It's also supposed to check whether the user_id passed has permission to actually create a project( i.e. isn't a standard user).
Here is the stored procedure:
USE [BugMate_DB]
GO
/****** Object: StoredProcedure [dbo].[create_project] Script Date: 2020-07-08 11:05:30 AM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE [dbo].[create_project]
#project_name NVARCHAR(40),
#date_started DATETIME,
#project_description NVARCHAR(400),
#project_status NVARCHAR(40),
#project_active BIT,
#next_iteration_date DATETIME,
#created_by_userid INT,
#project_leader_id INT,
#save_id INT = NULL
AS
SET NOCOUNT ON
BEGIN
IF (SELECT TOP 1 roleid from user_info WHERE userid = #created_by_userid) = 'SDU'
BEGIN
RAISERROR ('User does not have permission to do this action. Please contact a manager or administrator to resolve this issue.', 16, 1)
END
ELSE
BEGIN
INSERT INTO project(project_name, date_started, project_description, project_status, project_active, next_iteration_date, created_by_userid, project_leader_id)
VALUES (#project_name, #date_started, #project_description, #project_status, #project_active, #next_iteration_date, #created_by_userid, #project_leader_id)
IF ##ERROR <> 0
BEGIN
RAISERROR('Project creation insert failed.', 16, 1)
END
ELSE
BEGIN
IF #save_id != NULL
BEGIN
IF EXISTS (SELECT TOP 1 save_id FROM saved_project WHERE save_id = #save_id)
BEGIN
DELETE FROM saved_project WHERE save_id = #save_id
END
END
END
END
IF ##ERROR <> 0
BEGIN
RAISERROR('Error creating project', 16, 1)
END
ELSE
BEGIN
INSERT INTO project_member(userid, project_number)
VALUES (#created_by_userid, (SELECT project_number FROM project WHERE created_by_userid = #created_by_userid))
END
END
The problem is that I am getting this error when execute my SP:
Msg 512, Level 16, State 1, Procedure create_project, Line 48
Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.
I'm not sure why any of my sub queries would be returning multiple values.
Here are the values I am trying to pass:
USE [BugMate_DB]
GO
DECLARE #return_value int
EXEC #return_value = [dbo].[create_project]
#project_name = N'Test',
#date_started = N'12/25/2015 12:00:00 AM',
#project_description = N'This is a test.',
#project_status = N'InDevelopment',
#project_active = 1,
#next_iteration_date = N'12/25/2015 12:00:00 AM',
#created_by_userid = 19,
#project_leader_id = 19,
#save_id = NULL
SELECT 'Return Value' = #return_value
GO
I have tried using "TOP 1" to try and get a single value back but it doesn't seem to be what I'm looking for.
As far as I can tell this isn't an issue of joins either.
I'm new to SQL Server so any help would be appreciated.

Answer 1

Try changing this
IF ( SELECT TOP 1 roleid from user_info WHERE userid = #created_by_userid ) = 'SDU'
BEGIN
RAISERROR ( 'User does not have permission to do this action. Please contact a manager or administrator to resolve this issue.', 16, 1 )
END
To
IF NOT EXISTS ( SELECT * FROM user_info WHERE userid = #created_by_userid AND roleid = 'SDU' )
BEGIN
RAISERROR ( 'User does not have permission to do this action. Please contact a manager or administrator to resolve this issue.', 16, 1 )
END
Edit: Include explicit role access.
IF NOT EXISTS ( SELECT * FROM user_info WHERE userid = #created_by_userid AND roleid IN ( 'SDU', 'MNG', 'ADM ' ) )
BEGIN
RAISERROR ( 'User does not have permission to do this action. Please contact a manager or administrator to resolve this issue.', 16, 1 )
END
Update:
USE [BugMate_DB]
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE [dbo].[create_project]
#project_name NVARCHAR(40),
#date_started DATETIME,
#project_description NVARCHAR(400),
#project_status NVARCHAR(40),
#project_active BIT,
#next_iteration_date DATETIME,
#created_by_userid INT,
#project_leader_id INT,
#save_id INT = NULL
AS
BEGIN
SET NOCOUNT ON;
DECLARE #err INT = 0;
DECLARE #output TABLE ( project_number INT );
IF NOT EXISTS ( SELECT * FROM user_info WHERE userid = #created_by_userid AND roleid IN ( 'SDU', 'MNG', 'ADM ' ) )
BEGIN
RAISERROR ( 'User does not have permission to do this action. Please contact a manager or administrator to resolve this issue.', 16, 1 );
END
ELSE
BEGIN
INSERT INTO project (
project_name, date_started, project_description, project_status, project_active, next_iteration_date, created_by_userid, project_leader_id
)
OUTPUT inserted.project_number INTO #output
VALUES (
#project_name, #date_started, #project_description, #project_status, #project_active, #next_iteration_date, #created_by_userid, #project_leader_id
);
-- Capture error value.
SET #err = ##ERROR;
IF #err <> 0
BEGIN
RAISERROR ( 'Project creation insert failed.', 16, 1 );
END
ELSE
BEGIN
IF #save_id IS NULL
BEGIN
IF EXISTS ( SELECT * FROM saved_project WHERE save_id IS NULL )
BEGIN
DELETE FROM saved_project WHERE save_id IS NULL;
END
END
END
END
IF #err <> 0
BEGIN
RAISERROR ( 'Error creating project', 16, 1 );
END
ELSE
BEGIN
INSERT INTO project_member (
userid, project_number
)
VALUES (
#created_by_userid,
( SELECT project_number FROM #output )
);
END
END

Answer 2

Please compare the NULL values using IS NULL like below:
IF #save_id IS NULL
or
IF #save_id IS NOT NULL

Answer 3

I haven't seen this type of query before
INSERT INTO project_member(userid, project_number)
VALUES (#created_by_userid,
(SELECT project_number FROM project WHERE created_by_userid = #created_by_userid))
I would do either
INSERT INTO project_member(userid, project_number)
VALUES (#created_by_userid, #project_id)
if I were just inserting 2 values.
If inserting many values I would do SELECT and not VALUES.
If I were inserting maybe more that 1 row of values:
INSERT INTO project_member(userid, project_number)
SELECT created_by_userid, project_number FROM project
WHERE created_by_userid = #created_by_userid
Im just guessing since that is about line 46
Also, what sacse said about IF (#save_id IS NULL)
maybe there is an answer in there someplace