Auto increment syntax errors - sql

Question

Here's the code to my simple database:
CREATE TABLE [dbo].[User_Info] (
[Username] NVARCHAR (50) NOT NULL,
[Password] NVARCHAR (50) NOT NULL,
[Firstname] NVARCHAR (50) NOT NULL,
[Lastname] NVARCHAR (50) NOT NULL,
[Email] NVARCHAR (50) NOT NULL,
[Country] NVARCHAR (50) NOT NULL,
[Phone] NVARCHAR (50) NOT NULL,
[Gender] NVARCHAR (50) NOT NULL,
[Admin] INT NULL,
PRIMARY KEY CLUSTERED ([Username] ASC)
);
SELECT GO * from User_Info;
Alter table User_Info
add column id int NOT NULL auto_increment Unique Key;
The error for this CREATE is:
Only 1 statement is allowed per batch, such as 'GO', might be required between statements
and the error for the column is:
Incorrect syntax near 'column'
I need an auto ID system so I can progress with my site, how can I fix this mess?

Answer 1

Below code worked for me:
CREATE TABLE user_Info (
[admin] int IDENTITY(1,1) PRIMARY KEY,
[Username] NVARCHAR (50) NOT NULL,
[Password] NVARCHAR (50) NOT NULL,
[Firstname] NVARCHAR (50) NOT NULL,
[Lastname] NVARCHAR (50) NOT NULL,
[Email] NVARCHAR (50) NOT NULL,
[Country] NVARCHAR (50) NOT NULL,
[Phone] NVARCHAR (50) NOT NULL,
[Gender] NVARCHAR (50) NOT NULL,
);

Answer 2

The code for T-SQL is:
CREATE TABLE dbo.UserInfo (
UserName nvarchar(50) not null,
PRIMARY KEY CLUSTERED (UserName ASC)
);
SELECT * FROM UserInfo;
GO
ALTER TABLE dbo.UserInfo ADD id int not null IDENTITY(1,1);
However, it might be preferable to make id your primary key and add a constraint to user name if you want that to be unique.

Answer 3

You need to add a batch separator, and remove column keyword, and replace auto_increment Unique Key with identity(1,1) unique
CREATE TABLE [dbo].[User_Info] (
[Username] NVARCHAR (50) NOT NULL,
[Password] NVARCHAR (50) NOT NULL,
[Firstname] NVARCHAR (50) NOT NULL,
[Lastname] NVARCHAR (50) NOT NULL,
[Email] NVARCHAR (50) NOT NULL,
[Country] NVARCHAR (50) NOT NULL,
[Phone] NVARCHAR (50) NOT NULL,
[Gender] NVARCHAR (50) NOT NULL,
[Admin] INT NULL,
PRIMARY KEY CLUSTERED ([Username] ASC)
);
GO
SELECT * from User_Info;
GO
Alter table User_Info
add id int identity(1,1) not null unique;
GO

Answer 4

When adding the column, specify IDENTITY along the a UNIQUE constraint specification to ensure unique values independent of the primary key. The example below also specifies a constraint name, which is a best practice instead of auto-generated constraint names.
CREATE TABLE [dbo].[User_Info] (
[Username] NVARCHAR (50) NOT NULL,
[Password] NVARCHAR (50) NOT NULL,
[Firstname] NVARCHAR (50) NOT NULL,
[Lastname] NVARCHAR (50) NOT NULL,
[Email] NVARCHAR (50) NOT NULL,
[Country] NVARCHAR (50) NOT NULL,
[Phone] NVARCHAR (50) NOT NULL,
[Gender] NVARCHAR (50) NOT NULL,
[Admin] INT NULL,
PRIMARY KEY CLUSTERED ([Username] ASC)
);
ALTER TABLE dbo.User_Info
ADD id int NOT NULL IDENTITY CONSTRAINT UQ_User_Info_id UNIQUE;
GO