Thursday 21 June 2018

Auto Increment

Auto increment is used to  generate an unique, when a new record is inserted into a table.
If use a auto increment than increase by 1. 
In table sequence is increment automatically.
Auto increment ignore null value.

Syntax :-

CREATE TABLE table_name
(
Column_name int NOT NULL AUTO_INCREMENT,
Column_name1 varchar (50) NOT NULL,
Column_name2 varchar (50),
PRIMARY KEY (column_name)
);

Example :-

CREATE TABLE emp
(
Emp_id int NOT NULL AUTO_INCREMENT,
Emp_name varchar (50) NOT NULL,
City varchar (50),
PRIMARY KEY (Emp_id)
);

Insert rule are different 

INSERT INTO emp (emp_name, city)
VALUES
('Subham', 'Delhi'),
('Ankit', 'Mumbai');

INSERT INTO emp (emp_id, emp_name, city)
VALUES
(NULL, 'Subham', 'Delhi'),
(NULL, 'Ankit', 'Mumbai');

INSERT INTO emp (emp_id, emp_name, city)
VALUES
(NULL, 'Subham', 'Delhi'),
(1, 'Ankit', 'Mumbai');

Table:-


Use NULL VALUE





0 Comments:

Post a Comment

Popular Posts

Categories

AI (27) Android (24) AngularJS (1) Assembly Language (2) aws (17) Azure (7) BI (10) book (4) Books (113) C (77) C# (12) C++ (82) Course (60) Coursera (176) coursewra (1) Cybersecurity (22) data management (11) Data Science (85) Data Strucures (6) Deep Learning (9) Django (6) Downloads (3) edx (2) Engineering (14) Excel (13) Factorial (1) Finance (5) flutter (1) FPL (17) Google (18) Hadoop (3) HTML&CSS (46) IBM (25) IoT (1) IS (25) Java (92) Leet Code (4) Machine Learning (43) Meta (18) MICHIGAN (4) microsoft (3) Pandas (3) PHP (20) Projects (29) Python (726) Python Coding Challenge (170) Questions (2) R (70) React (6) Scripting (1) security (3) Selenium Webdriver (2) Software (17) SQL (40) UX Research (1) web application (8)

Followers

Person climbing a staircase. Learn Data Science from Scratch: online program with 21 courses