In SQL, data types can be divided into Char and Varchar. But are you aware of the difference between Char and Varchar data types? If not, then don’t worry. You are at the right place. In this article, we will discuss the difference between char and varchar.
The main difference between char and varchar is that the char data type stores characters of a fixed length. On the other hand, the Varchar data type stores characters of variable length.
Before diving deeper into the topic (difference between char and varchar), let’s quickly go through the list of topics listed under the table of contents (TOC) we will cover in this article.
Table of Content
- Difference Between Char and Varchar
- What is Char Data Type?
- Example of Char
- What is Varchar Data Type?
- Example of Varchar
- Key Differences Between Char and Varchar
Difference Between Char and Varchar
For a better understanding, let’s explore the difference between char and varchar in a tabular format. Here’s the table:
|Stands for||Char stands for “Character.”||Varchar stands for “Variable Character.”|
|Use||Stores characters or strings of a fixed length (size).||Stores characters or strings of a variable length (size).|
|Storage size||Is equal to n bytes, i.e., set length.||Is equal to the actual length of the entered string in bytes.|
|Performance||Provides better performance in comparison to Varchar.||Provides inferior performance as length has to be accounted for.|
|Padding||Pad space is required when storing strings less than the fixed size length.||No padding is required as it is variable in size.|
|Byte||Takes 1 byte for each character.||Takes 1 byte for each character, and in addition to that, it also takes some extra bytes for holding length information.|
|Best to use it||When we expect the data values in a column to be of the same length||When we expect the data values in a column to be of variable length.|
What is Char Data Type?
Definition: Char is a data type in SQL that allows storing a character string of fixed length specified.
The storage size of the Char is n bytes. So, a CHAR(1000) field (or variable) takes up 1000 bytes on a disk, regardless of the string it holds. This data type is best used when you expect the data values in a column to be the same length.
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The syntax for declaring a CHAR column is as follows:
CREATE TABLE table_name ( column_name CHAR(n) );
Example of Char
Suppose you declare a variable of char (10) data type; it will always take 10 bytes of data regardless of whether you store one character, five characters, seven characters, or ten characters. It will always take 10 bytes, i.e., you can store a maximum of 10 characters in a column. Due to this, sometimes, a lot of database space is wasted.
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What is Varchar Data Type?
Definition: Varchar is a data type in SQL that allows you to store character strings of variable length but a maximum of the set length specified.
Varchar only uses the space it needs to store the string and will not be padded with spaces, as was the case when using the Char data type. One of the main advantages of using VARCHAR over CHAR is that it can save space in the database because it only uses the amount needed to store the actual data and not a fixed amount of space for all rows, regardless of the length of the stored string.
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The syntax for declaring a Varchar column is as follows:
CREATE TABLE table_name ( column_name VARCHAR(n) );
Example of Varchar
Suppose you declare a variable of varchar (10) data type; then it will use the number of bytes equal to the number of characters. So, storing two characters will take two bytes; if you are storing five characters, it will take 5 bytes, and so on. Due to this, much database space is saved, which was wasted when using the Char data type.
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Key Differences Between Char and Varchar
Here are the key differences between Char and Varchar data types:
- Char has a fixed size, but varchar has a variable size.
- Char data type stores data of fixed length, whereas the Varchar data type stores variable format data.
- Varchar data type values are not padded with spaces; char values are padded with spaces to the specified length.
- Char uses a fixed amount of space for each value, regardless of the length of the stored string. In contrast, varchar only uses the space needed to store the data.
- Char is best used when you expect the data values in a column to be the same length. On the other hand, varchar is best used when you expect the data values in a column to be of variable length.
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In this article, we have discussed all there is to know regarding the difference between char and varchar data types. If you have any queries related to the topic, please feel free to send your queries to us through a comment. We will be happy to help you.
Can CHAR and VARCHAR store the same maximum number of characters?
No, CHAR and VARCHAR have different maximum lengths. The maximum length of a CHAR column is fixed, while the maximum length of a VARCHAR column can vary based on the database implementation.
Does the storage length affect the performance of queries?
The storage length can affect the performance of queries. Since VARCHAR uses variable-length storage, it may require additional processing to determine the length of each stored value, which can slightly impact performance compared to CHAR.
Can CHAR and VARCHAR be used interchangeably?
While both data types store character data, they are not interchangeable. You should choose the appropriate data type based on the specific requirements of your data, such as fixed-length vs. variable-length storage needs.
Can CHAR or VARCHAR be used for storing numeric data?
CHAR and VARCHAR are primarily designed for storing character data, not numeric data. For numeric data, it is recommended to use appropriate numeric data types such as INT, FLOAT, etc.
Which data type is more suitable for storing textual data?
VARCHAR is generally more suitable for storing textual data because it allows for variable-length storage, which can save space when dealing with variable-length strings.
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