What's the difference between VARCHAR and CHAR?

VARCHAR is variable-length.

CHAR is fixed length.

If your content is a fixed size, you'll get better performance with CHAR.

See the MySQL page on CHAR and VARCHAR Types for a detailed explanation (be sure to also read the comments).

CHAR

1. Used to store character string value of fixed length.
2. The maximum no. of characters the data type can hold is 255 characters.
3. It's 50% faster than VARCHAR.
4. Uses static memory allocation.

VARCHAR

1. Used to store variable length alphanumeric data.
2. The maximum this data type can hold is up to
   • Pre-MySQL 5.0.3: 255 characters.
   • Post-MySQL 5.0.3: 65,535 characters shared for the row.
3. It's slower than CHAR.
4. Uses dynamic memory allocation.

CHAR Vs VARCHAR

CHAR is used for Fixed Length Size Variable
VARCHAR is used for Variable Length Size Variable.

E.g.

Create table temp
(City CHAR(10),
Street VARCHAR(10));

Insert into temp
values('Pune','Oxford');

select length(city), length(street) from temp;

Output will be

length(City)          Length(street)
10                    6

Conclusion: To use storage space efficiently must use VARCHAR Instead CHAR if variable length is variable