How to change programmatically non-identity column to identity one? - sql

I have a table with column ID that is identity one. Next I create new non-identity column new_ID and update it with values from ID column + 1. Like this:
new_ID = ID + 1
Next I drop ID column and rename new_ID to name 'ID'.
And how to set Identity on this new column 'ID'?
I would like to do this programmatically!

As far as I know, you have to create a temporary table with the ID field created as IDENTITY, then copy all the data from the original table. Finally, you drop the original table and rename the temporary one. This is an example with a table (named TestTable) that contains only one field, called ID (integer, non IDENTITY):
BEGIN TRANSACTION
GO
CREATE TABLE dbo.Tmp_TestTable
(
ID int NOT NULL IDENTITY (1, 1)
) ON [PRIMARY]
GO
SET IDENTITY_INSERT dbo.Tmp_TestTable ON
GO
IF EXISTS(SELECT * FROM dbo.TestTable)
EXEC('INSERT INTO dbo.Tmp_TestTable (ID)
SELECT ID FROM dbo.TestTable WITH (HOLDLOCK TABLOCKX)')
GO
SET IDENTITY_INSERT dbo.Tmp_TestTable OFF
GO
DROP TABLE dbo.TestTable
GO
EXECUTE sp_rename N'dbo.Tmp_TestTable', N'TestTable', 'OBJECT'
GO
COMMIT

Looks like SQL Mobile supports altering a columns identity but on SQL Server 2005 didn't like the example from BOL.
So your options are to create a new temporary table with the identity column, then turn Identity Insert on:
Create Table Tmp_MyTable ( Id int identity....)
SET IDENTITY_INSERT dbo.Tmp_Category ON
INSERT Into Tmp_MyTable (...)
Select From MyTable ....
Drop Table myTable
EXECUTE sp_rename N'dbo.Tmp_MyTable', N'MyTable', 'OBJECT'
Additionally you can try and add the column as an identity column in the first place and then turn identity insert on. Then drop the original column. But I am not sure if this will work.

Guessing you didn't have much luck with your task....
In table design, you should be able to go into properties and under Identity Specification change (Is Identity) to Yes and assign the column primary key if it formerly had the primary key.

From SqlServerCentral.com
Changing from Non-IDENTITY to IDENTITY and vice versa

An Identity is a property that is set at the time the table is created or a new column is added in alter table statement. You can't alter the column and set it to identity and it is impossible to have two identity columns within the same table.
Depending on the size of the table, is it possible to simply create a new table? copy over the schema of the old one and then use SET IDENTITY_INSERT ON to populate the new identity column with what you want from the old one.

Related

Update identity column sql [duplicate]

I have a MS SQL 2005 database with a table Test with column ID. ID is an identity column.
I have rows in this table and all of them have their corresponding ID auto incremented value.
Now I would like to change every ID in this table like this:
ID = ID + 1
But when I do this I get an error:
Cannot update identity column 'ID'.
I've tried this:
ALTER TABLE Test NOCHECK CONSTRAINT ALL
set identity_insert ID ON
But this does not solve the problem.
I need to have identity set to this column, but I need to change values as well from time to time. So my question is how to accomplish this task.
You need to
set identity_insert YourTable ON
Then delete your row and reinsert it with different identity.
Once you have done the insert don't forget to turn identity_insert off
set identity_insert YourTable OFF
IDENTITY column values are immutable.
However it is possible to switch the table metadata to remove the IDENTITY property, do the update, then switch back.
Assuming the following structure
CREATE TABLE Test
(
ID INT IDENTITY(1,1) PRIMARY KEY,
X VARCHAR(10)
)
INSERT INTO Test
OUTPUT INSERTED.*
SELECT 'Foo' UNION ALL
SELECT 'Bar' UNION ALL
SELECT 'Baz'
Then you can do
/*Define table with same structure but no IDENTITY*/
CREATE TABLE Temp
(
ID INT PRIMARY KEY,
X VARCHAR(10)
)
/*Switch table metadata to new structure*/
ALTER TABLE Test SWITCH TO Temp;
/*Do the update*/
UPDATE Temp SET ID = ID + 1;
/*Switch table metadata back*/
ALTER TABLE Temp SWITCH TO Test;
/*ID values have been updated*/
SELECT *
FROM Test
/*Safety check in case error in preceding step*/
IF NOT EXISTS(SELECT * FROM Temp)
DROP TABLE Temp /*Drop obsolete table*/
In SQL Server 2012 it is possible to have an auto incrementing column that can also be updated more straightforwardly with SEQUENCES
CREATE SEQUENCE Seq
AS INT
START WITH 1
INCREMENT BY 1
CREATE TABLE Test2
(
ID INT DEFAULT NEXT VALUE FOR Seq NOT NULL PRIMARY KEY,
X VARCHAR(10)
)
INSERT INTO Test2(X)
SELECT 'Foo' UNION ALL
SELECT 'Bar' UNION ALL
SELECT 'Baz'
UPDATE Test2 SET ID+=1
Through the UI in SQL Server 2005 manager, change the column remove the autonumber (identity) property of the column (select the table by right clicking on it and choose "Design").
Then run your query:
UPDATE table SET Id = Id + 1
Then go and add the autonumber property back to the column.
Firstly the setting of IDENTITY_INSERT on or off for that matter will not work for what you require (it is used for inserting new values, such as plugging gaps).
Doing the operation through the GUI just creates a temporary table, copies all the data across to a new table without an identity field, and renames the table.
This can be done using a temporary table.
The idea
disable constraints (in case your id is referenced by a foreign key)
create a temp table with the new id
delete the table content
copy back data from the copied table to your original table
enable previsously disabled constraints
SQL Queries
Let's say your test table have two additional columns (column2 and column3) and that there are 2 tables having foreign keys referencing test called foreign_table1 and foreign_table2 (because real life issues are never simple).
alter table test nocheck constraint all;
alter table foreign_table1 nocheck constraint all;
alter table foreign_table2 nocheck constraint all;
set identity_insert test on;
select id + 1 as id, column2, column3 into test_copy from test v;
delete from test;
insert into test(id, column2, column3)
select id, column2, column3 from test_copy
alter table test check constraint all;
alter table foreign_table1 check constraint all;
alter table foreign_table2 check constraint all;
set identity_insert test off;
drop table test_copy;
That's it.
DBCC CHECKIDENT ( ‘databasename.dbo.orders’,RESEED, 999)
you can change any identity column number with this command,and also you can start that field number from every number you want.for example in my command i ask to start from 1000 (999+1)
hope that it would be enough...good luck
If the column is not a PK you could always create a NEW column in the table with the incremented numbers, drop the original and then alter the new one to be the old.
curious as to why you might need to do this... most I've ever had to futz with Identity columns was to backfill numbers and I just ended up using DBCC CHECKIDENT ( tablename,RESEED,newnextnumber)
good luck!
Identity modifying may fail depending on a number of factors, mainly revolving around the objects/relationships linked to the id column. It seems like db design is as issue here as id's should rarely if ever change (i'm sure you have your reasons and are cascasding the changes). If you really need to change id's from time to time, I'd suggest either creating a new dummy id column that isn't the primary key/autonumber that you can manage yourself and generate from the current values. Alternately, Chrisotphers idea above would be my other suggestion if you're having issues with allowing identity insert.
Good luck
PS it's not failing because the sequential order it's running in is trying to update a value in the list to an item that already exists in the list of ids? clutching at straws, perhaps add the number of rows+1, then if that works subtract the number of rows :-S
If you need to change the IDs occasionally, it's probably best not to use an identity column. In the past we've implemented autonumber fields manually using a 'Counters' table that tracks the next ID for each table. IIRC we did this because identity columns were causing database corruption in SQL2000 but being able to change IDs was occasionally useful for testing.
You can insert new rows with modified values and then delete old rows. Following example change ID to be same as foreign key PersonId
SET IDENTITY_INSERT [PersonApiLogin] ON
INSERT INTO [PersonApiLogin](
[Id]
,[PersonId]
,[ApiId]
,[Hash]
,[Password]
,[SoftwareKey]
,[LoggedIn]
,[LastAccess])
SELECT [PersonId]
,[PersonId]
,[ApiId]
,[Hash]
,[Password]
,[SoftwareKey]
,[LoggedIn]
,[LastAccess]
FROM [db304].[dbo].[PersonApiLogin]
GO
DELETE FROM [PersonApiLogin]
WHERE [PersonId] <> ID
GO
SET IDENTITY_INSERT [PersonApiLogin] OFF
GO
First save all IDs and alter them programmatically to the values you wan't, then remove them from database and then insert them again using something similar:
use [Name.Database]
go
set identity_insert [Test] ON
insert into [dbo].[Test]
([Id])
VALUES
(2)
set identity_insert [Test] OFF
For bulk insert use:
use [Name.Database]
go
set identity_insert [Test] ON
BULK INSERT [Test]
FROM 'C:\Users\Oscar\file.csv'
WITH (FIELDTERMINATOR = ';',
ROWTERMINATOR = '\n',
KEEPIDENTITY)
set identity_insert [Test] OFF
Sample data from file.csv:
2;
3;
4;
5;
6;
If you don't set identity_insert to off you will get the following error:
Cannot insert explicit value for identity column in table 'Test' when
IDENTITY_INSERT is set to OFF.
I saw a good article which helped me out at the last moment .. I was trying to insert few rows in a table which had identity column but did it wrongly and have to delete back. Once I deleted the rows then my identity column got changed . I was trying to find an way to update the column which was inserted but - no luck. So, while searching on google found a link ..
Deleted the columns which was wrongly inserted
Use force insert using identity on/off (explained below)
http://beyondrelational.com/modules/2/blogs/28/posts/10337/sql-server-how-do-i-insert-an-explicit-value-into-an-identity-column-how-do-i-update-the-value-of-an.aspx
Very nice question, first we need to on the IDENTITY_INSERT for the specific table, after that run the insert query (Must specify the column name).
Note: After edit the the identity column, don't forget to off the IDENTITY_INSERT. If you not done, you cannot able to Edit the identity column for any other table.
SET IDENTITY_INSERT Emp_tb_gb_Menu ON
INSERT Emp_tb_gb_Menu(MenuID) VALUES (68)
SET IDENTITY_INSERT Emp_tb_gb_Menu OFF
http://allinworld99.blogspot.com/2016/07/how-to-edit-identity-field-in-sql.html

Add identity increment property to existing tables at once

I have multiple tables in database all table has id column which is primary key.
I want a script by which i can add identity property to all tables at once rather than I go and change one by one.
You can't alter the existing columns for identity.
You have 2 options:
Create a new table with identity & drop the existing table
Create a new column with identity & drop the existing column
But take spl care when these columns have any constraints / relations.
For already craeted table Names
Drop table Names
Create table Names
(
ID int,
Name varchar(50)
)
Insert Into Names Values(1,'SQL Server')
Insert Into Names Values(2,'ASP.NET')
Insert Into Names Values(4,'C#')
In this Approach you can retain the existing data values on the newly
created identity column
CREATE TABLE dbo.Tmp_Names
(
Id int NOT NULL IDENTITY (1, 1),
Name varchar(50) NULL
) ON [PRIMARY]
go
SET IDENTITY_INSERT dbo.Tmp_Names ON
go
IF EXISTS(SELECT * FROM dbo.Names)
INSERT INTO dbo.Tmp_Names (Id, Name)
SELECT Id, Name FROM dbo.Names TABLOCKX
go
SET IDENTITY_INSERT dbo.Tmp_Names OFF
go
DROP TABLE dbo.Names
go
Exec sp_rename 'Tmp_Names', 'Names'
In this approach you can’t retain the existing data values on the
newly created identity column;
The identity column will hold the sequence of number
Alter Table Names Add Id_new Int Identity(1,1)
Go
Alter Table Names Drop Column ID
Go
Exec sp_rename 'Names.Id_new', 'ID','Column'
Source 1
What you can do is write a quick query to generate the SQL for you
like so:
USE INFORMATION_SCHEMA;
SELECT
CONCAT("ALTER TABLE `", TABLE_SCHEMA,"`.`", TABLE_NAME, "` CONVERT TO CHARACTER SET UTF8;")
AS MySQLCMD FROM TABLES
WHERE TABLE_SCHEMA = "your_schema_goes_here";
Then you can run the output from this to do what you need.
Source 2
EDIT
You could check Altering Multiple Tables at once

How to Alter a table for Identity Specification is identity SQL Server

not working
ALTER TABLE ProductInProduct ALTER COLUMN Id KEY IDENTITY (1, 1);
Check Image
I have a table ProductInProduct is want its id should be Unique..
You cannot "convert" an existing column into an IDENTITY column - you will have to create a new column as INT IDENTITY:
ALTER TABLE ProductInProduct
ADD NewId INT IDENTITY (1, 1);
Update:
OK, so there is a way of converting an existing column to IDENTITY. If you absolutely need this - check out this response by Martin Smith with all the gory details.
You can't alter the existing columns for identity.
You have 2 options,
Create a new table with identity & drop the existing table
Create a new column with identity & drop the existing column
Approach 1. (New table) Here you can retain the existing data values on the newly created identity column.
CREATE TABLE dbo.Tmp_Names
(
Id int NOT NULL
IDENTITY(1, 1),
Name varchar(50) NULL
)
ON [PRIMARY]
go
SET IDENTITY_INSERT dbo.Tmp_Names ON
go
IF EXISTS ( SELECT *
FROM dbo.Names )
INSERT INTO dbo.Tmp_Names ( Id, Name )
SELECT Id,
Name
FROM dbo.Names TABLOCKX
go
SET IDENTITY_INSERT dbo.Tmp_Names OFF
go
DROP TABLE dbo.Names
go
Exec sp_rename 'Tmp_Names', 'Names'
Approach 2 (New column) You can’t retain the existing data values on the newly created identity column, The identity column will hold the sequence of number.
Alter Table Names
Add Id_new Int Identity(1, 1)
Go
Alter Table Names Drop Column ID
Go
Exec sp_rename 'Names.Id_new', 'ID', 'Column'
See the following Microsoft SQL Server Forum post for more details:
http://social.msdn.microsoft.com/forums/en-US/transactsql/thread/04d69ee6-d4f5-4f8f-a115-d89f7bcbc032
You don't set value to default in a table. You should clear the option "Default value or Binding" first.

SQL Server 2008: ALTER TABLE query

I am getting error for the below code
ALTER TABLE ADM_Roles ALTER COLUMN RoleID int IDENTITY (1, 1)
Incorrect syntax near the keyword IDENTITY.
You cannot change an existing column into an IDENTITY column - you will need to add a new column that has the identity flag:
ALTER TABLE dbo.ADM_Roles
ADD NewRoleID INT IDENTITY (1, 1)
If you need to, you can later on drop the old column and rename the new column to the old name:
ALTER TABLE dbo.ADM_Roles DROP COLUMN RoleID
EXEC sp_rename #objName = 'dbo.ADM_Roles.NewRoleID',
#newName = 'RoleID',
#objType = 'COLUMN'
From the MSDN
You can't alter the existing columns for identity.
You have 2 options,
Create a new table with identity & drop the existing table
Create a new column with identity & drop the existing column But
take special care when these columns have any constraints / relations.
Example approach:
In this approach you can’t retain the existing data values on the newly created identity column;
The identity column will hold the sequence of number
Alter Table Names Add Id_new Int Identity(1,1)
Go
Alter Table Names Drop Column ID
Go
Exec sp_rename 'Names.Id_new', 'ID','Column'
you have to remove the word "int".
ALTER TABLE ADM_Roles ALTER COLUMN RoleId IDENTITY (1, 1);

Can a sql server table have two identity columns?

I need to have one column as the primary key and another to auto increment an order number field. Is this possible?
EDIT: I think I'll just use a composite number as the order number. Thanks anyways.
CREATE TABLE [dbo].[Foo](
[FooId] [int] IDENTITY(1,1) NOT NULL,
[BarId] [int] IDENTITY(1,1) NOT NULL
)
returns
Msg 2744, Level 16, State 2, Line 1
Multiple identity columns specified for table 'Foo'. Only one identity column per table is allowed.
So, no, you can't have two identity columns. You can of course make the primary key not auto increment (identity).
Edit: msdn:CREATE TABLE (Transact-SQL) and CREATE TABLE (SQL Server 2000):
Only one identity column can be created per table.
You can use Sequence for second column with default value IF you use SQL Server 2012
--Create the Test schema
CREATE SCHEMA Test ;
GO
-- Create a sequence
CREATE SEQUENCE Test.SORT_ID_seq
START WITH 1
INCREMENT BY 1 ;
GO
-- Create a table
CREATE TABLE Test.Foo
(PK_ID int IDENTITY (1,1) PRIMARY KEY,
SORT_ID int not null DEFAULT (NEXT VALUE FOR Test.SORT_ID_seq));
GO
INSERT INTO Test.Foo VALUES ( DEFAULT )
INSERT INTO Test.Foo VALUES ( DEFAULT )
INSERT INTO Test.Foo VALUES ( DEFAULT )
SELECT * FROM Test.Foo
-- Cleanup
--DROP TABLE Test.Foo
--DROP SEQUENCE Test.SORT_ID_seq
--DROP SCHEMA Test
http://technet.microsoft.com/en-us/library/ff878058.aspx
Add one identity column and then add a computed column whose formula is the name of the identity column
Now both will increment at the same time
No it is not possible to have more than one identity column.
The Enterprise Manager does not even allow you to set > 1 column as identity. When a second column is made identity
Also note that ##identity returns the last identity value for the open connection which would be meaningless if more than one identity column was possible for a table.
create table #tblStudent
(
ID int primary key identity(1,1),
Number UNIQUEIDENTIFIER DEFAULT NEWID(),
Name nvarchar(50)
)
Two identity column is not possible but if you accept to use a unique identifier column then this code does the same job as well. And also you need an extra column - Name column- for inserting values.
Example usage:
insert into #tblStudent(Name) values('Ali')
select * from #tblStudent
Ps: NewID() function creates a unique value of type uniqueidentifier.
The primary key doesn't need to be an identity column.
You can't have two Identity columns.
You could get something close to what you want with a trigger...
in sql server it's not possible to have more than one column as identity.
I've just created a code that will allow you inserting two identities on the same table. let me share it with you in case it helps:
create trigger UpdateSecondTableIdentity
On TableName For INSERT
as
update TableName
set SecondIdentityColumn = 1000000+##IDENTITY
where ForstId = ##IDENTITY;
Thanks,
A workaround would be to create an INSERT Trigger that increments a counter.
So I have a table that has one identity col : applicationstatusid. its also the primary key.
I want to auto increment another col: applicationnumber
So this is the trigger I write.
create trigger [applicationstatus_insert] on [ApplicationStatus] after insert as
update [Applicationstatus]
set [Applicationstatus].applicationnumber =(applicationstatusid+ 4000000)
from [Applicationstatus]
inner join inserted on [applicationstatus].applicationstatusid = inserted.applicationstatusid