I have a table with autoincremented primary key. In my code I am trying to receive the new autoincremented value when I execute each 'insert' query. Is there a way to do it programatically?
Thanks.
UPD:
Assume I have a table:
TABLE User ( userID INT NOT NULL AUTO_INCREMENT, name VARCHAR( 25 ) NOT NULL , email VARCHAR( 50 ) NOT NULL , UNIQUE ( userID ) );
And I when I insert new values (name and email) to this table I want automatically receive newly generated userID. Ideally I am looking for any ways to do that with a single transaction and without stored procedures.
Have your sql/stored proc return scope_identity() or if you are using Linq2SQL or EF the entity used for insertion gets the new id.
In the stored proc it is:
ALTER proc [dbo].[SaveBuild](
#ID int = 0 output,
#Name varchar(150)=null,
#StageID int,
#Status char(1)=null
)
as
SET NOCOUNT ON
Insert into Builds
(name, StageID, status)
values (#Name, #StageID, #Status)
select #ID = scope_identity()
RETURN #ID
In the C# code you have:
public int SaveBuild(ref int id, ref string Name)
{
SqlCommand cmd = GetNewCmd("dbo.SaveBuild");
cmd.Parameters.Add("#ID", SqlDbType.Int).Value = id;
cmd.Parameters["#ID"].Direction = ParameterDirection.InputOutput;
cmd.Parameters.Add("#Name", SqlDbType.VarChar).Value = Name;
cmd.Parameters.Add("#StageID", SqlDbType.Int).Value = 0;
ExecuteNonQuery(cmd);
id = (int)cmd.Parameters["#ID"].Value;
return id;
}
Dependent upon your situation, you might be better off using table-valued parameters to pass your inserts to a stored procedure, then use OUTPUT INSERTED to return a table-valued parameter from your stored procedure.
It will drastically reduce the number of hits required if you're processing multiple items.
Are you limited to building SQL on the client and sending it to the server? Cause if you can use a stored procedure, this is easy to do. In the stored proc, do the insert and then, either
Select Scope_Identity() as the last statement in the stored proc., or
Use a output parameter to the stored proc, (say named #NewPKValue) and make the last statement:
Set #NewPKValue = Scope_Identity()
Otherwise, you need to send a batch of commands to the server that include two statements, the insert, and Select Scope_Identity() and execute the batch as though it was a select statement
You could use the SQL statement SELECT scope_identity().
Related
I have a Windows application written in C# using embedded firebird sql version 2.5.5.26952, which I am re-working it to update to embedded firebird sql version 4.0.0.2496. I have update the fdb file to the new version,and all the tables and sprocs, are there. When run a cmd.Fill() command for a selected statement rows are returned, if I do a update for a row in the table, I get the expected results back fine. but If I do a insert nothing is returned, and no errors are thrown, but the data is added to the database. If I run the sproc from the FireRobin application, the data is inserted, and a row is returned, so I'm at a loss to know why it is not working from my C# application. below is slimmed down version of the code.
The 2.5 version is using FirebirdSql.Data.FirebirdClient.4.10.0.0
The 4.0 version is using FirebirdSql.Data.FirebirdClient.9.0.2
using (var cmd = new FbDataAdapter("PROC_UPSERTPEOPLE", _connection)
{
DataTable data = new DataTable();
cmd.SelectCommand.Parameters.Add("SURNAME", FbDbType.Text).Value = item.Surname;
cmd.SelectCommand.Parameters.Add("FORENAMENAME", FbDbType.Text).Value = item.Forename);
var transaction = _connection.BeginTransaction();
cmd.SelectCommand.CommandType = CommandType.StoredProcedure;
cmd.SelectCommand.Transaction = transaction;
var result = cmd.Fill(data);
transaction.Commit();
}
On a update result contains 1, and data has the expected result, but on a insert result = 0, and data has no rows in.
Any help would be appreciated.
This is the simple version fo the sproc in question
CREATE OR ALTER PROCEDURE PROC_UPSERTPEOPLE_SLIM
(
RECID INTEGER,
SURNAME VARCHAR(100),
FORENAME VARCHAR(100)
)
RETURNS
(
ID INTEGER,
LSURNAME VARCHAR(100),
LFORENAME VARCHAR(100)
)
AS
DECLARE VARIABLE local_id integer;
DECLARE VARIABLE local_surname varchar(100);
DECLARE VARIABLE local_forename varchar(100);
BEGIN
select
ID,
FORENAME,
SURNAME
FROM
APA_PEOPLE
WHERE
(:RECID IS NOT NULL AND ID = :RECID)
OR (:RECID IS NULL
AND FORENAME = :FORENAME
AND SURNAME = :SURNAME)
INTO
:local_id,
:local_forename,
:local_surname;
IF (:local_id IS NULL) then
begin
UPDATE OR INSERT INTO APA_PEOPLE(FORENAME, SURNAME)
VALUES(:FORENAME, :SURNAME)
MATCHING (FORENAME, SURNAME);
end
else
begin
UPDATE APA_PEOPLE SET FORENAME = :FORENAME,
SURNAME = :SURNAME
WHERE ID = :local_id;
end
FOR
SELECT
ID,
SURNAME,
FORENAME
from
APA_PEOPLE
WHERE
(:RECID IS NOT NULL AND ID = :RECID)
OR (:RECID IS NULL
AND FORENAME = :FORENAME
AND SURNAME = :SURNAME)
INTO
:ID,
:LSURNAME,
:LFORENAME
DO
begin
suspend;
end
END;
Update
To answer my own question, being mainly a TSQL developer, DSQL seems strange, change the sproc to the following, which is simpler
CREATE OR ALTER PROCEDURE PROC_UPSERTPEOPLE_SLIM (
RECID integer,
SURNAME varchar(100),
FORENAME varchar(100)
)
RETURNS (ID integer)SQL SECURITY INVOKER
AS
BEGIN
UPDATE OR INSERT INTO APA_PEOPLE(FORENAME, SURNAME)
VALUES(:FORENAME, :SURNAME)
MATCHING (FORENAME, SURNAME)
RETURNING ID INTO :ID;
END;
but also had to change the way it was called, to use
EXECUTE PROCEDURE PROC_UPSERTPEOPLE_SLIM(#RECID, #SURNAME, #FORENAME)
This does seem counter intuitive, I had assumed a stored procedure was a stored procedure, and there are not two different flavors. Oh well it works now, so move on to getting the rest of the app to work.
I have created a stored procedure for SQL Server 2014.
There are two parameters: Name which is a user name and Hash which is password md5 hash. I check in the database if the md5 hashes are equal (first hash is from the program and the second one is already stored in the database).
If I just run a query (not a stored procedure) in the database (or in program using commandType.Text) - everything works and the user is being selected, but when I run the exact thing but using stored procedures, the SqlReader in C# has no elements returned, which most likely means that the conditions during those variable comparison were not met.
Maybe I am doing something wrong?
I also have about 10 other stored procedures for reading or/and writing to the database, everything works except this one.
Here is the procedure:
CREATE PROCEDURE GetHash
#Name nvarchar(50),
#Hash nvarchar(200)
AS
BEGIN
SET NOCOUNT ON;
SELECT Orders.orderId, Employee.name, Employee.surname
FROM Orders
LEFT JOIN Employee ON Orders.orderId = Employee.id
WHERE batchName = '#Name' AND productCode = '#Hash'
END
GO
Code part:
public Boolean VerifyPassword(string name, string password)
{
var paramsList = new List<SqlParameter> { new SqlParameter("#Name", name), new SqlParameter("#Hash", GetMd5Hash(password)) };
const string ProcedureName = "GetHash";
var ActiveUser = new DBController().GetFromDatabase(ProcedureName, "Login", "EJL15_DB", paramsList).ToList();
return ActiveUser.Count > 0;
}
And from Database Controller
private void SetCommandProperties(string procedureName, IEnumerable<SqlParameter> paramsList)
{
this.sqlCommand.CommandText = procedureName;
this.sqlCommand.CommandType = CommandType.StoredProcedure;
foreach (var curParam in paramsList)
this.sqlCommand.Parameters.Add(curParam);
this.sqlCommand.CommandTimeout = 15;
}
You don't need to quote the parameters in the stored procedure. Do this instead:
CREATE PROCEDURE GetHash
#Name nvarchar(50),
#Hash nvarchar(200)
AS
BEGIN
SET NOCOUNT ON;
SELECT Orders.orderId,
Employee.name,
Employee.surname
FROM Orders
LEFT JOIN Employee
ON Orders.orderId=Employee.id
WHERE batchName = #Name
AND productCode = #Hash
END
I just wonder, obviously your #Hash parameter passed to the stored
procedure is a user's password. But for some reason your WHERE clause
in the procedure goes like that:
"WHERE batchName='#Name' AND productCode='#Hash'"
Is there a chance your condition is incorrect? I guess it should be something like: Employee.password = #Hash
You should not put '' around your variables. Otherwise your comparison is totally wrong.
I have two tables and I need to update values in them via a stored procedure. Tried too much to update but some times it update the first table only, others the second or even fail due to cannot allow duplicates. Also when it updates the WHOLE data in the table becomes the same as the new updated ones. I've now reached to this error after all these lines of codes
Cannot insert the value NULL into column 'Emp_ID',table 'DatePics'; column does not allow nulls. UPDATE fails.The statement has been terminated
Here is the SQL code :
ALTER procedure [dbo].[UpdateEmp]
#EmpName nvarchar(100),
#Nationality nvarchar(30),
#Passport nvarchar(20),
#ContractDate date,
#HealthDate date
AS
BEGIN
set nocount on;
DECLARE #IDs table (ID int )
UPDATE Employee SET
EmpName=#EmpName, Nationality=#Nationality, Visa=#Visa, Passport=#Passport,
ReceivedDate=#ReceivedDate,IDIssue=#IDIssue, IDExpiry=#IDExpiry, Sponsor=#Sponsor
output inserted.ID into #IDs (ID)
WHERE ID = #ID
UPDATE DatePics SET
FingerDate=#FingerDate, ContractDate=#ContractDate, HealthDate=#HealthDate
where Emp_ID in (select ID from #IDs);
END
After writing the stored procedure code, I wrote the C# code like this:
private void updatebtn_Click(object sender, EventArgs e)
{
SqlCommand cmd = new SqlCommand();
cmd.Connection = db.con;
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "UpdateEmp";
cmd.Parameters.AddWithValue("#EmpName", NameSeartxt.Text);
cmd.Parameters.AddWithValue("#Nationality", NatSeartxt.Text);
cmd.Parameters.AddWithValue("#Passport", PassSeartxt.Text);
cmd.Parameters.AddWithValue("#ContractDate", ContractSeartxt.Text);
cmd.Parameters.AddWithValue("#HealthDate", HealthSeartxt.Text);
db.con.Open();
int up = cmd.ExecuteNonQuery();
if (up > 0)
{
MessageBox.Show("Update done ", "DONE !");
SearNametxt.Text = "";
}
else
{
MessageBox.Show("Failed to update", "FAIL !");
SearNametxt.Text = "";
}
db.con.Close();
}
Any clue?
I can see three problems with your query. 1 You declare ID, but don't assign it before using it, so it will always be NULL for the first query, so this will never update any rows:
DECLARE #ID int
UPDATE FrstTable SET
EmpName=#EmpName, Nationality=#Nationality, Passport=#Passport
WHERE ID = #ID
Secondly, you are using SCOPE_IDENTITY to attempt to get the ID of the record that has been updated. You can't do that, SCOPE_IDENTITY will return the last inserted ID, it is not affected by updates. You will need to use OUTPUT to get the Updated ID:
DECLARE #IDs TABLE (ID INT);
UPDATE FirstTable
OUTPUT inserted.ID INTO #Ids (ID)
SET EmpName = #EmpName,
Nationality = #Nationality,
Passport = #Passport;
Thirdly, your second update statement has no where clause, so will update the entire table:
UPDATE ScndTable
SET Emp_ID=#ID, ContractDate=#ContractDate, HealthDate=#HealthDate
WHERE EmpID IN (SELECT ID FROM #Ids);
Your stored procedure looks weird to me. I believe there should be a WHERE cluase for the second UPDATE otherwise it will always update the whole ScndTable table. set #ID = SCOPE_IDENTITY(); seems to be reduntant here. Are you trying to perform insert into ScndTable if there's no corresponding Emp_ID there? Finnaly explicitly create a transaction to update either both tables or none.
Hope it helps!
Please assign the value of #ID variable, before executing the first update statement.
I think you are trying to update some row, so you can pass the 'id' value from the CSHARP code. When you use the SCOPE_IDENTITY, you will get the last inserted value. Try to pass the ID value from the front end.
Hi i'm having trouble with inserting incremented userid inside my db below is my table,stored proc,and my code.
CREATE TABLE [dbo].[Assignment2]
(
userID int PRIMARY KEY IDENTITY(1,1),
Name varchar(255) NOT NULL,
Age int NOT NULL,
Hobbies varchar(255)
)
and a stored procedure
ALTER PROCEDURE [db].[p_Assignment2_ins]
#userID int,
#Name nvarchar(100),
#Age int,
#Hobbies nvarchar(100)
AS
INSERT INTO [DB].[db].[Assignment2]
([Name]
,[Age]
,[Hobbies])
VALUES
(#Name
,#Age
,#Hobbies)
If ##Error <> 0
Return -1
Select #userID = ##Identity // this one just get the latest id that we inserted right?
Return 0
I have some question :
I want to know how do we insert the UserID from the code behind because If the table is empty at first shouldn't we insert a data first into the table
How do we generate an AutoIncrementID from codebehind and insert it
SqlConnection conn = new SqlConnection(ts.ConnMethod());
SqlCommand cmd = new SqlCommand("p_Assignment2_ins", conn);
cmd.CommandType = CommandType.StoredProcedure;
//I'm missing how we should add the IncrementedID
cmd.Parameters.AddWithValue("#Name", TextBox1.Text);
cmd.Parameters.AddWithValue("#Age", TextBox2.Text);
cmd.Parameters.AddWithValue("#Hobbies", TextBox3.Text);
conn.Open();
cmd.ExecuteNonQuery();
conn.Close();
Any help is really appreciated thanks
Select #userID = ##Identity // this one just get the latest id that we inserted right?
No, you should use SCOPE_IDENTITY(). ##Identity returns the last id, yes, but not the last id from your insert. If you have a trigger, for example, that also produces an insert on a another table as a result of your insert, you will get the id inserted on the other table by that trigger.
Here's a nice article explaining the differences.
As far as inserting autoincrement values on your table; you can't do this unless you disable the constraint first but in essence, this shouldn't be necessary unless you are doing some sort of data import. In your scenario, you should be able to just insert values on the other columns except the identity field with autoincrement. The database will take care of inserting the appropriate value for you.
If you have AUTOINCREMENT field, you SHOULD NOT insert and generate values at all. DB is doing all by itself. So, remove the code that inserts ID-s
I am currently working in C#, and I need to insert a new record into one table, get the new primary key value, and then use that as a foreign key reference in inserting several more records. The Database is MS SQL Server 2003. All help is appreciated!
The way to get the identity of the inserted row is with the SCOPE_IDENTITY() function. If you're using stored procedures then this would look something like the following to return the row identity as an output parameter.
CREATE PROCEDURE dbo.MyProcedure
(
#RowId INT = NULL OUTPUT
)
AS
INSERT INTO MyTable
(
Column1
,Column2
,...
)
VALUES
(
#Param1
,#Param2
,...
);
SET #RowId = SCOPE_IDENTITY();
You can then use this value for any subsequent inserts (alternatively, if you can pass the data all into the stored procedure, then you can use it in the remainder of the procedure body).
If you're passing the SQL in dynamically then you use much the same technique, but with a single string with statement delimiters (also ; in SQL), e.g.:
var sql = "INSERT INTO MyTable (Column1, Column2, ...) VALUES (#P1, #P2, ...);" +
"SELECT SCOPE_IDENTITY();";
Then if you execute this using ExecuteScalar you'll be able to get the identity back as the scalar result and cast it to the right type. Alternatively you could build up the whole batch in one go, e.g.
var sql = "DECLARE #RowId INT;" +
"INSERT INTO MyTable (Column1, Column2, ...) VALUES (#P1, #P2, ...);" +
"SET #RowId = SCOPE_IDENTITY();" +
"INSERT INTO MyOtherTable (Column1, ...) VALUES (#P3, #P4, ...);";
This may not be exactly the right syntax, and you may need to use SET NOCOUNT ON; at the start (my mind is rusty as I rarely use dynamic SQL) but it should get you on the right track.
The best way of doing this is the use SCOPE_IDENTITY() function in TSQL. This should be executed as part of the insert i.e.
SqlCommand cmd = new SqlCommand(#"
INSERT INTO T (Name) VALUES(#Name)
SELECT SCOPE_IDENTITY() As TheId", conn);
cmd.AddParameter("#Name", SqlDbType.VarChar, 50).Value = "Test";
int tId = (int)cmd.ExecuteScalar();
Alternatively you can assign SCOPE_IDENTITY() to a variable to be used in successive statements. e.g.
DECLARE #T1 int
INSERT INTO T (Name) VALUES('Test')
SELECT #T1 = SCOPE_IDENTITY()
INSERT INTO T2 (Name, TId) VALUES('Test', #T1)
If you are just using SQL then check Duncan's answer. If however you are using LINQ then you can create the entity, save it to the DB and the ID parameter will be populated automatically.
Given a user entity and a user table it might look like this:
using(var db = new DataContext()) {
var user = new User { Name = "Jhon" };
db.Users.InsertOnSubmit(user);
db.SubmitChanges();
/* At this point the user.ID field will have the primary key from the database */
}