

- Trending Categories
Data Structure
Networking
RDBMS
Operating System
Java
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
what are the different attributes of MySQL ENUM data type?
MySQL ENUM types can be defined with following attributes that affect the allowed values −
- NOT NULL − In ENUM type, by default NULL values are allowed. To disallow NULL values, we need to use the NOT NULL attribute while describing the ENUM column.
- NULL − The NULL attribute is a synonym for DEFAULT NULL. The index value for NULL is NULL.
- DEFAULT − The DEFAULT attribute causes an ENUM data type to have a default value when a value is not specified. In other words, we can say that INSERT statement does not have to include a value for this field because if it does not include then the value following DEFAULT will be inserted. Functions are not allowed in the DEFAULT expression. For ENUM data type the DEFAULT values include NULL and empty string (‘’).
Example
Following example will show the use of these attributes with ENUM data type.
mysql> SET SESSION sql_mode = ''; Query OK, 0 rows affected (0.00 sec) mysql> Create Table enumtesting(e_value ENUM('a','1')NOT NULL DEFAULT '1',id TINYINT NOT NULL); Query OK, 0 rows affected (0.23 sec) mysql>Insert into enumtesting(e_value,id)values('1','1'),('',2),(NULL,3),('abc',4); Query OK, 4 rows affected, 3 warnings (0.09 sec) Records: 4 Duplicates: 0 Warnings: 3 mysql> show warnings; +---------+------+----------------------------------------------------+ | Level | Code | Message | +---------+------+----------------------------------------------------+ | Warning | 1265 | Data truncated for column 'e_value' at row 2 | | Warning | 1048 | Column 'e_value' cannot be null | | Warning | 1265 | Data truncated for column 'e_value' at row 4 | +---------+------+----------------------------------------------------+ 3 rows in set (0.00 sec) mysql> Select * from enumtesting; +----+---------+ | e_value | id | +---------+----+ | 1 | 1 | | | 2 | | | 3 | | | 4 | +---------+----+ 4 rows in set (0.00 sec) mysql> insert into enumtesting(id) values(5); Query OK, 1 row affected (0.11 sec) mysql> Select * from enumtesting; +---------+----+ | e_value | id | +---------+----+ | 1 | 1 | | | 2 | | | 3 | | | 4 | | 1 | 5 | +---------+----+ 5 rows in set (0.00 sec) mysql> select e_value, e_value+0 AS enum_index, id from enumtetsing; +---------+------------+----+ | e_value | enum_index | id | +---------+------------+----+ | 1 | 2 | 1| | | 0 | 2| | | 0 | 3| | | 0 | 4| | 1 | 2 | 5| +---------+------------+----+ 5 rows in set (0.00 sec)
- Related Questions & Answers
- What is MySQL ENUM data type? What are the advantages to use ENUM data type?
- Explain attributes and the different types of attributes in DBMS?
- Add a new value to a column of data type enum in MySQL?
- What are the different quote marks of MySQL?
- How can I insert default value in MySQL ENUM data type?
- The equals and == operator for Enum data type in Java
- What are the different types of MySQL GENERATED COLUMNS?
- What are the different data types of arrays in C#?
- What are the DataTransfer object attributes?
- What are the attributes in C#?
- What are different Perl Data Types?
- Does SQL Server have an equivalent to MySQL's ENUM data type?
- MySQL data types int versus enum?
- What are the attributes of a Perfect Capital Market?
- What are different types of data in C language?
Advertisements