Table of contents

Introduction

Understanding VARCHAR and NVARCHAR

2.1.

VARCHAR

2.2.

NVARCHAR

Key Differences between VARCHAR and NVARCHAR

Advantages and Disadvantages

4.1.

Advantages of VARCHAR

4.2.

Disadvantages of VARCHAR

4.3.

Advantages of NVARCHAR

4.4.

Disadvantages of NVARCHAR

Best Practices

Frequently Asked Questions

6.1.

Is it better to use NVARCHAR or VARCHAR?

6.2.

How to compare NVARCHAR to VARCHAR in SQL Server?

6.3.

What is the maximum size of VARCHAR?

6.4.

What is the size of Nvarchar?

6.5.

When should I use VARCHAR instead of NVARCHAR?

6.6.

Can I mix VARCHAR and NVARCHAR columns in the same table?

6.7.

How do I convert between VARCHAR and NVARCHAR data types in SQL?

Conclusion

Last Updated: Mar 25, 2025

Easy

Difference between VARCHAR and NVARCHAR

Author Rashmi

Do you think IIT Guwahati certified course can help you in your career?

Yes

Introduction

In the world of relational databases, choosing the right data type for storing text data is crucial for both performance and storage efficiency. VARCHAR and NVARCHAR are two commonly used data types for storing variable-length, non-binary character strings. While these data types share similarities, they have significant differences that can impact your database's performance and storage requirements.

This article will explore the key differences between VARCHAR and NVARCHAR, discussing their use cases, advantages, and disadvantages, as well as providing examples, best practices and answering frequently asked questions.

Also see, SQL EXCEPT

Understanding VARCHAR and NVARCHAR

In this section, we will understand VARCHAR and NNVARCHAR.

VARCHAR

VARCHAR (short for variable character) is a data type used to store non-Unicode variable-length character strings. This means that it can store characters from a single-byte character set, such as ASCII. The maximum length of a VARCHAR column can be specified during table creation or modification, up to a maximum of 8,000 characters.

Example of defining a VARCHAR column:

CREATE TABLE Employee (
    EmployeeID INT PRIMARY KEY,
    FirstName VARCHAR(50),
    LastName VARCHAR(50)
);

NVARCHAR

NVARCHAR (short for national variable character) is a data type used to store Unicode variable-length character strings. Unicode is a character encoding standard that allows for the representation of a wide range of characters, including those from different languages and scripts. Like VARCHAR, the maximum length of an NVARCHAR column can be specified during table creation or modification, up to a maximum of 4,000 characters.

Example of defining an NVARCHAR column:

CREATE TABLE Employee (
    EmployeeID INT PRIMARY KEY,
    FirstName NVARCHAR(50),
    LastName NVARCHAR(50)
);

Key Differences between VARCHAR and NVARCHAR

The key difference between VARCHAR and NVARCHAR are:-

VARCHAR	NVARCHAR
VARCHAR uses a single-byte character set, meaning it can store characters from a single language or script.	NVARCHAR uses Unicode, allowing it to store characters from multiple languages and scripts.
VARCHAR stores each character using a single byte,	NVARCHAR columns typically consume twice as much storage space as equivalent VARCHAR columns.
The maximum length of VARCHAR and NVARCHAR columns also differs. VARCHAR columns can store up to 8,000 characters.	NVARCHAR columns can store up to 4,000 characters.

VARCHAR

NVARCHAR

VARCHAR uses a single-byte character set, meaning it can store characters from a single language or script.

NVARCHAR uses Unicode, allowing it to store characters from multiple languages and scripts.

VARCHAR stores each character using a single byte,

NVARCHAR columns typically consume twice as much storage space as equivalent VARCHAR columns.

The maximum length of VARCHAR and NVARCHAR columns also differs. VARCHAR columns can store up to 8,000 characters.

NVARCHAR columns can store up to 4,000 characters.

Advantages and Disadvantages

The advantages and disadvantages of VARCHAR and NVARCHAR are:-

Advantages of VARCHAR

Storage Efficiency: VARCHAR requires less storage space than NVARCHAR, making it more efficient for storing text data from a single language or script.

Performance: Due to its smaller storage requirements, VARCHAR can offer better performance for certain operations, such as string manipulation and sorting.

Disadvantages of VARCHAR

Limited Language Support: VARCHAR can only store characters from a single-byte character set, limiting its usefulness for storing multilingual text data.

Encoding Inconsistency: The character encoding used by VARCHAR may vary across platforms and systems, leading to potential encoding issues.

Advantages of NVARCHAR

Multilingual Support: NVARCHAR supports a wide range of characters from different languages and scripts, making it more suitable for storing multilingual text data.

Consistency: By using Unicode, NVARCHAR ensures consistent character encoding across different platforms and systems.

Disadvantages of NVARCHAR

Increased Storage Space: NVARCHAR requires more storage space than VARCHAR, potentially leading to higher storage costs and reduced performance for certain operations.

Best Practices

Assess Your Application Requirements: Before choosing between VARCHAR and NVARCHAR, consider the specific requirements of your application, such as the languages and scripts you need to support, storage efficiency, and performance concerns. Evaluate your text data storage needs carefully and choose the data type that best aligns with your application's requirements.

Consider Future Expansion: When designing your database, think about potential future expansion and the possibility of needing to support additional languages or scripts. Choosing NVARCHAR from the outset may save time and effort in the long run if you anticipate your application will need to handle multilingual data in the future.

Optimize Database Performance: Monitor and analyze your database's performance to identify any potential bottlenecks or inefficiencies related to the use of VARCHAR and NVARCHAR columns. Optimize your database design, queries, and indexing strategies to ensure the best possible performance.

Test for Encoding Issues: When working with VARCHAR data types, be mindful of potential encoding issues that may arise when transferring data between different systems or platforms. Implement appropriate data validation and testing procedures to identify and resolve any encoding inconsistencies.

Frequently Asked Questions

Is it better to use NVARCHAR or VARCHAR?

Use NVARCHAR when dealing with text in multiple languages (Unicode characters) to ensure compatibility. Use VARCHAR for single-language text where character encoding isn't a concern, as it's more storage-efficient.

How to compare NVARCHAR to VARCHAR in SQL Server?

To compare NVARCHAR and VARCHAR in SQL Server, consider encoding needs. Use NVARCHAR for multilingual support and VARCHAR for single language, which is more storage-efficient and faster for certain operations.

What is the maximum size of VARCHAR?

In SQL Server, the maximum size of a VARCHAR column is 8,000 characters. However, this limit can be extended to 1,073,741,824 characters by using the "MAX" specifier.

What is the size of Nvarchar?

In SQL Server, the size of an NVARCHAR column depends on the specified length. It can store up to 4,000 Unicode characters, and you can use "MAX" for up to 2^30-1 characters.

When should I use VARCHAR instead of NVARCHAR?

Use VARCHAR when you only need to store text data from a single language or script, and storage efficiency and performance are critical considerations for your database.

Can I mix VARCHAR and NVARCHAR columns in the same table?

Yes, you can mix VARCHAR and NVARCHAR columns in the same table. However, be mindful of the potential performance implications and storage space differences when doing so.

How do I convert between VARCHAR and NVARCHAR data types in SQL?

To convert between VARCHAR and NVARCHAR data types, you can use the CAST or CONVERT functions in SQL. For example: CONVERT(NVARCHAR, your_varchar_column) or CAST(your_varchar_column AS NVARCHAR).

Conclusion

In summary, the key difference between VARCHAR and NVARCHAR lies in the character encoding they use and the resulting storage space requirements. VARCHAR is more suitable for storing text data from a single language or script, offering better storage efficiency and performance. In contrast, NVARCHAR supports a wide range of characters from different languages and scripts, making it ideal for storing multilingual text data.