SQL

create table sql server auto increment primary key

/* mysql server */
CREATE TABLE persons (
    id int NOT NULL AUTO_INCREMENT,
    colour varchar(191) NOT NULL,
    created datetime, 
    modifed datetime
);

/* sql server IDENTITY*/
CREATE TABLE persons (
    id int IDENTITY(1,1) PRIMARY KEY,
    colour varchar(191) NOT NULL,
    created datetime, 
    modifed datetime
);

INSERT INTO persons (colour, created, modified)
VALUES ('red','2022-08-05', '2022-08-05'),
VALUES ('green','2022-08-05', '2022-08-05'),
VALUES ('blue','2022-08-05', '2022-08-05');

create table with primary key auto increment in sql

CREATE TABLE table_name (
    id INT NOT NULL IDENTITY(1, 1),
    name NVARCHAR (100) NULL,
    school NVARCHAR (100) NULL,
    PRIMARY KEY (ID)
);

SQL Auto Increment Primary Key - SQL Server

-- using IDENTITY(x, y) to auto increment the value
-- x -> start value, y -> steps to increase
CREATE TABLE Colleges (
  college_id INT IDENTITY(1,1),
  college_code VARCHAR(20) NOT NULL,
  college_name VARCHAR(50),
  CONSTRAINT CollegePK PRIMARY KEY (college_id)
);

-- inserting record without college_id
INSERT INTO Colleges(college_code, college_name)
VALUES ("ARD13", "Star Public School");

add primary key with auto increment sql server

/*
--Syntax for MySQL
MySQL uses the AUTO_INCREMENT keyword to perform an auto-increment feature.
By default, the starting value for AUTO_INCREMENT is 1, and it will increment by 1 for each new record.
*/
CREATE TABLE Persons (
    Personid int NOT NULL AUTO_INCREMENT,
    LastName varchar(255) NOT NULL,
    FirstName varchar(255),
    Age int,
    PRIMARY KEY (Personid)
);

/* Syntax for SQL Server: */
CREATE TABLE Persons (
    Personid int IDENTITY(1,1) PRIMARY KEY,
    LastName varchar(255) NOT NULL,
    FirstName varchar(255),
    Age int
);

/* Syntax for Oracle: */
CREATE SEQUENCE seq_person
MINVALUE 1
START WITH 1
INCREMENT BY 1
CACHE 10;