Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How to insert auto_increment in an already created table in MySQL?
Use ALTER command for this. Let us first create a table −
mysql> create table DemoTable -> ( -> StudentName varchar(100) -> ); Query OK, 0 rows affected (0.46 sec)
Here is the query to insert auto_increment −
mysql> alter table DemoTable ADD COLUMN StudentId int NOT NULL; Query OK, 0 rows affected (0.50 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> alter table DemoTable ADD PRIMARY KEY(StudentId); Query OK, 0 rows affected (1.23 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> alter table DemoTable CHANGE StudentId StudentId int NOT NULL AUTO_INCREMENT; Query OK, 0 rows affected (2.20 sec) Records: 0 Duplicates: 0 Warnings: 0
Insert some records in the table using insert command −
mysql> insert into DemoTable(StudentName) values('Chris');
Query OK, 1 row affected (0.17 sec)
mysql> insert into DemoTable(StudentName) values('David');
Query OK, 1 row affected (0.15 sec)Display all records from the table using select statement
mysql> select *from DemoTable;
Output
This will produce the following output −
+-------------+-----------+ | StudentName | StudentId | +-------------+-----------+ | Chris | 1 | | David | 2 | +-------------+-----------+ 2 rows in set (0.00 sec)
Updated on: 30-Jun-2020
158 Views
Advertisements