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guvencum

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AutoInc in SQL Server

How can i create a field like autoincrement in Access ?
I want to have a serial number e.g. 1 to 9999999 and while appending a new record it automatically increments itself by one. I think it is done by Identity , but how? How is it used. Explanations are appreciated..
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odessa

CREATE TABLE dbo.TEST (
      ID int IDENTITY (1, 1) NOT NULL ,
..
)
GO

Where you set IDENTITY to be ID field autoincrement, first 1 stands for starting value, second for step, field must be not null
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ASKER

I already created an identity field like it but, i use a TTable in Delphi and bounded it to a dbgrid. When i want to insert a record, it didn't put ID field a value. And when i post, it gave me an error "ID field must have a value". (I know it must have a value. And you were supposed to give it!...) When i identify ID field as Identity, i have to make it not null. This is why SQL Server gives error message. SQL Server must put a value in ID field automatically, and when i post it must save this autoincremented value in ID field. when i did it by a TQuery with SQL statement like this it worked "insert mytable1(name,surname) values('Izzet','Altinmese')". But when i did it by TTable, it didn't work. Now i use a dummy table to store last record's id. And i autoincrement it by myself in program. But i'm not sure if tens of people enters record, if it locks the record by itself (SQL Server), or do i have to do it by myself again ( by semaphores..etc.). If i do all these things, what will SQL Server do ?!...
I faced a similar problem (in Visual Basic ). I solved it by using following code
begin transaction1
Begin transaction2
insert mytable1(name,surname) values('Izzet','Altinmese')
end transaction2
retrieve identity column value by using max(identity column) function and a where clause like name = "Izzet" and surname = "Altinmese"

eg. select max(identity col) from table1 where name =  "Izzet" and surname = "Altinmese"

this is not foolproof but it should work for most of the cases
if it works for you i will upgrade my comments to answer.

Best of luck,
Manish77

sorry for error in previos code please use this one
I faced a similar problem (in Visual Basic ). I solved it by using following code

begin transaction

insert mytable1(name,surname) values('Izzet','Altinmese')
end transaction

retrieve identity column value by using max(identity column) function and a where clause like name = "Izzet" and surname = "Altinmese"

eg. select max(identity col) from table1 where name =  "Izzet" and surname = "Altinmese"

this is not foolproof but it should work for most of the cases
if it works for you i will upgrade my comments to answer.

Best of luck,
Manish77
It seems to work .
But It is something bring extra oversheads to the server
my application must be so optimized .
I already change my mind not to use data bounded controls and TTable.
Nevertheless thanks for your comment.
Change it to answer and let me appreciate it

best of luck
guvencum
guvencum
Please reject the answer from Odessa and unlock this question so that I can post it as a answer.
Thanx,
Manish
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manish77

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