I have a table named emp with the following columns:
id int (autoincrement),
name varchar,
maxid int
I want to insert id, name, and maxid where maxid should be the value of autoincrement id.
Out of the two query options below, which one is best option and why?
option 1:
insert into emp (name,maxid) values ('abc',(select max(id)+1 from emp))
option 2:
string QRY = "insert into emp values('abc',0) select scope_identity()";
sqlcommand cmd= new sqlcommand(QRY, con);
datatable dt = new datatable();
con.open();
dt.load(cmd.executereader());
con.close();
int scopeid=int.parse(dt.rows[0][0].tostring());
QRY="update emp set maxid='"+scopeid+"' where id ='"+scopeid+"'";
cmd= new sqlcommand(QRY, con);
cmd.executenonquery();
easy way to do Demo is here
insert dbo.emp
select 'abc', IDENT_CURRENT('dbo.emp')
None of above are correct implementation of update.
But according to your scenario i would do two things.
First insert the names and use the auto increment to set the id and after that perform update no those records that do not have set yet the maxId.
Why do this in two stages ?
It is possible that we could have different result from MAX(id) and value of id set by incremental feature by database, so option 1 must be drop.
The query that could be used.
insert into emp (name) values ('abc')
update emp set maxid = id where maxid is null;
But from other hand and Serge observation, you should entirely drop this behavior if possible. Another alternative is to crate a trigger that kick after insert. Advantage of this is that above view or computed column is that you perform this operation only once.
I'll rather use INSERT INTO...SELECT statement,
INSERT INTO emp (name, maxid)
SELECT 'abc', COALESCE(MAX(id), 0) + 1
FROM emp
Select max(id)+1 could be different from autoincrement id so that option is not valid.
As for the second option it's still unnecessary complication. You can just insert with maxid NULL and then update to id
insert into emp (name,maxid) values ('abc',NULL)
update emp set maxid = id where maxid is null
Related
I have an table name dbo.EmpInfo having 4 columns
1-UserId 2-SubUserId 3-Year 4-Status
I have an another table (in other database) name dbo.EmpInfo1 having 4 columns
1-UserId 2-SubUserId 3-Year 4-Status
UserId may be repeating in both tables..
Now i have to find those UserId from Both tables whose Status="Success" and this status count is < 10 and bind these values in Gridview..
for ex-I have an UserId say mayank#gmail.com and in dbo.EmpInfo it has status count=5(Status="Success") and in dbo.EmpInfo1 it has status count=7 so from both tables the total count for mayank#gmail.com is 12 so we have to bind this userId in Gridview. and Gridview having all the above columns..
i have a procedure -
ALTER proc [dbo].[sp_countUserDetails]
as
begin try
begin transaction
Select distinct(UserId) from EmpInfo where Status='Success'
union all
Select distinct(UserId) from MyDB.dbo.EmpInfo1 where Status='Sucess'
commit transaction
end try
in my .cs file i used
SqlDataReader dr = ms.sp_SelectExecuter("sp_countUserDetails");
DataTable dt = new DataTable();
dt.Load(dr);
foreach (DataRow DR in dt.Rows)
{
ms = new MethodStore();
ms.sp_SelectExecuter("sp_usercount", "#userid", (DR["UserId"]).ToString());
}
and the Procedure is-
ALTER Procedure [dbo].[sp_usercount]
#userid varchar(50)
as
declare #count1213 dec =0, #count1314 dec =0;
begin try
begin transaction
select #count1314= count(UserId) from EmpInfo where Status='Status' and UserID=#userid;
select #count1213= count(UserId) from MyDB.dbo.EmpInfo1 where Status='Success' and UserID=#userid;
select #count1213+#count1314 as 'Count'
if((#count1213+#count1314)>=10)
insert into MyTaxCafe.dbo.demo values (#userid);
commit transaction
end try
bt the table dbo.demo doesn't contain distinct UserId..because our Procedure
[dbo].[sp_countUserDetails]
give Distinct values from both table but at due to Union there is an redundancy can we control it because Same UserId may be Exist in both tables
First you need a SQL to query two database , you may try it like this
SELECT Status FROM [database1].[dbo].[TableName] AS t1 INNER JOIN [database2].[dbo].[TableName] AS t2
ON (t1.UserId = t2.UserId)
WHERE Status='Success'
GROUP BY Status
Having COUNT(Status) < 10
in your C# code , use SqlDataAdapter to fill DataTable,
then set DataGridView's field DataSource = DataTable
You must use union from your query to get expected result.
Your columns are same in both tables so u can use union without any changes
for example
select * (select * from TableName1
where Status = 'Success'
union
select * from TableName2
where Status = 'Success'
) A
where count(Status)<10
group by SubUserId, Year, Status
try this.
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.
I am attempting to insert the record into m sql database. My very first value is 1 then 1001. My insert will place the first value which is 1 correctly but 1001 and beyond it returns null. How can I change this to read the value and not use the index since it does not go in sequential order?
Insert Method:
SqlCommand addJob = new SqlCommand(#"INSERT INTO JobNumber ( JobID, CustomerID, JobDescription, IsActive) VALUES ( #JobID, (SELECT #CustomerID FROM Customer C WHERE C.CustomerID = #CustomerID), #JobDescription, #IsActive)", dbConn);
addJob.Parameters.AddWithValue("#JobID", Convert.ToInt32(jobidTextBox.Text));
addJob.Parameters.AddWithValue("#CustomerID", Convert.ToInt32(customeridComboBox.SelectedIndex) + 1);
addJob.Parameters.AddWithValue("#JobDescription", jobdescriptionTextBox.Text);
addJob.Parameters.AddWithValue("#IsActive", isactiveCheckBox.Checked);
dbConn.Open();
addJob.ExecuteNonQuery();
Try selected text/ selected item property of the combo-box instead of the index.
you should retrieve your text item like this
addJob.Parameters.AddWithValue("#CustomerID", Convert.ToInt32(customeridComboBox.Items[customeridComboBox.SelectedIndex+ 1] );
I have this kind of method on inserting data
private void InsertReceipt()
{
decimal Stub;
Stub = Math.Floor(decimal.Parse(txtAmount.Text) / 2000);
SqlCommand cmd = new SqlCommand();
cmd.Connection = cn;
cmd.CommandType = CommandType.Text;
cmd.CommandText = "INSERT INTO Ticket(CustomerID, Date, Store, Amount, NoStub)" +
"VALUES (#CustomerID, #Date, #Store, #Amount, #NoStub) ";
cmd.Parameters.AddWithValue("#CustomerID", txtCustomerID.Text);
cmd.Parameters.AddWithValue("#Date", dtpDate.Value.Date.ToString());
cmd.Parameters.AddWithValue("#Store", txtStore.Text);
decimal amount = decimal.Parse(txtAmount.Text);
cmd.Parameters.AddWithValue("#Amount", amount);
cmd.Parameters.Add("#NoStub", SqlDbType.Decimal).Value = Stub;
cmd.ExecuteNonQuery();
}
I just want to have a method that if you insert a data in table "Ticket" there's another table will be updating.
CustomerID Date Store Amount NoStub
1 6/7/2013 Nike 4000 2
2 6/7/2013 Adidas 6000 3
This table will be updating, for example I will be using table named "StubRange", This output will be generate.
RangeID CustomerID NoStub TickerStart TickerEnd
1 1 2 00001 00002
2 2 3 00003 00005
I just want to learned how to have this kind of kind of method.
What you are looking for is an After Insert trigger.
Basically you can think of it as an event that triggers after an insert takes place (hence trigger...).
Your trigger should look something like:
CREATE TRIGGER YourTriggerName --The name of your trigger
ON Ticket --The table it will be observing
AFTER INSERT,UPDATE --It will trigger after insert / update
AS
--The actions you want to do. For example:
DECLARE #CustomerId int
SET #CustomerId = (SELECT CustomerId FROM inserted) --you might want to use 'inserted' table
--Inset values
Insert into StubRange (CustomerID , NoStub)
Select Distinct ins.CustomerID, ins.NoStub
From Inserted ins
--Update existing records
UPDATE StubRange
set --Set what ever it is you want to update
WHERE CustomerId = #CustomerId
More about Inserted table - According to Microsoft:
The inserted table stores copies of the affected rows during INSERT
and UPDATE statements. During an insert or update transaction, new
rows are added to both the inserted table and the trigger table. The
rows in the inserted table are copies of the new rows in the trigger
table.
Well you need to write a insert trigger when ever you insert record in Ticket table. You can refer below syntax to create trigger. This is a Oracle syntax
CREATE OR REPLACE TRIGGER TRIGGER_INSERT_STUBRANGE
AFTER INSERT ON TICKET
FOR EACH ROW
DECLARE
raise_exception Exception;
BEGIN
--WRITE YOUR INSERT STATEMENT HERE
Exception
when raise_exception then
RAISE_APPLICATION_ERROR(-20001, sqlerrm );
END;
This will create an insert trigger on your table1 on updating table1 , table2 will b updated with CustomerID, NoStub from table 1 and rest of properties depends on your business logic
CREATE TRIGGER trig_Update_table
ON [tableName1]
FOR INSERT
AS
Begin
Insert into tableName2 (CustomerID , NoStub)
Select Distinct i.CustomerID, i.NoStub
from Inserted i
End
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 */
}