Introduction
Following the advent of computers, demand for new and diverse programming and computer languages arose. Different computer languages arrived with a variety of codes and data kinds to meet the needs of the users. SQL is the most often used and taught programming language. This is how programmers store different strings of data of various lengths. The data types 'char' and 'varchar' are two of the most regularly used.
Both are data types in many programming languages and database systems, with char denoting a single character and varchar denoting a variable character. The character type char in C is used to store string values, primarily UTF-8 encoded characters and integers. Varchar, on the other hand, is a data type that may hold indefinitely long data of any type. Varchar is a field's data type in a database management system. While they can both hold strings up to 8,000 characters in length, char requires more storage than varchar. They are both used to store the same types of data, but the way they are saved and retrieved differs. Let's have a look at the distinctions between them.
Char VS Varchar
The fundamental distinction between Char and Varchar is that char only stores fixed-length single-string data types, whereas varchar stores variable characters of various strings, the length of which is determined by the string. The SQL data type Char stands for 'characters' and is used to store characters. Only non-Unicode data, i.e., only one type of string per cell, is stored. It also has a set length, which can range from 1-to 255 characters.
Varchar is another SQL data type that can be used to store variable-length characters. 'Variable character' is what it stands for. It stores alphanumeric data, and the size is determined by the string being stored.
In programming languages and database systems, the data types 'Char' and 'Varchar' have certain similarities in terms of usefulness and technicality. They do, however, differ significantly in terms of how they are kept and accessed. While char denotes a single character, varchar denotes a variable character. Char is a fixed-length data type, but varchar is a variable-length data type, as the name implies. Char uses up to one byte per character, whereas varchar takes up to one byte per character plus an additional one or two bytes for length information. The length of a char can range from 0 to 255, while the length of varchar can range from 0 to 65,535.
In programming languages and database systems, the data types 'Char' and 'Varchar' have certain similarities in terms of usefulness and technicality. They do, however, differ significantly in terms of how they are kept and accessed.
While char denotes a single character, varchar denotes a variable character. Char is a fixed-length data type, but varchar is a variable-length data type, as the name implies. Char uses up to one byte per character, whereas varchar takes up to one byte per character plus an additional one or two bytes for length information. The length of a char can range from 0 to 255, while the length of varchar can range from 0 to 65,535.
Because char is a fixed-length variable, all empty spaces in the field are filled with blanks. Varchar, on the other hand, has a variable length and only stores the characters you specify. When the values are saved in 'char' fields, the remaining characters are padded with white spaces, whereas 'varchar' does not add extra spaces when the data is less than the given length.
Difference Between Char and Varchar in tabular form
| Parameters of Comparison | Char | Varchar |
| Explanation | It's a SQL code that aids in character storage. | It's a SQL function that aids in the storage of variable characters. |
| Abbreviation | character | Variable |
| Storage | They store fixed-length values that are equal to the column's maximum. | They store variable data in an alphanumeric format and are dependent on the string that is recorded. |
| Memory | Static memory allocation | Dynamic memory allocation |
| Bytes used | One byte | 1 byte per character, plus 1 or 2 extra bytes for storing information of various lengths. |
| Character limit | 255 characters | 65535 characters |
| Uses | When the length of the characters is compact and known, programmers can leverage this. | When the length of the data entries varies, programmers can leverage this. |
| Content | Only characters | Contains a variety of strings, including characters and variables. |
What is Char?
Char is a fixed-value data type that stores non-Unicode data values. 'Char' is what it stands for. Only when the length of data storage is known is it employed by programmers. They have a maximum character limit of 255 characters and the storage capacity is the same as the storage size for the column because they only store one type of string. In addition, they store each character with one byte. They use static memory allocation, which means the variable's storage is permanent and the memory has already been allocated before the codes are input and performed.
The term Char comes from the fact that it is a fixed-length data type that is used to store non-Unicode characters (short for character). Each letter encoded as a number — those from the ASCII encoding – takes up one byte of memory. Small integers can also be declared using the char type. The keyword 'char' is used to declare a character variable, which means a single character is kept in one byte.
Char can be signed or unsigned, just like integers. It can carry signed char values ranging from -128 to 127, and it can also be unsigned, holding values ranging from 0 to 255, depending on the architectural size. Char values are right-padded with spaces to the specified length when stored.
What is Varchar?
Variable characters are stored in the Varchar data type. 'Variable character' is what it stands for. They are used by programmers when the data length varies and more than one data type is required. Because they have distinct strings, their maximum character limit is 65,535 characters, which varies depending on the character limit of each string. They, like char, use one byte per character. They do, however, take an extra 1 or 2 bytes to store length information.
They dynamically allocate memory. When the length or amount of data to be saved is uncertain or variable, this is utilized. It also allows you to save data without having to worry about exceeding a certain amount. They are used to store information such as addresses. Varchar is a variable-length data type that can hold any sort of data with a length ranging from 0 and 65,535 characters. Depending on the database, the Varchar field can store values of any size up to a specific maximum. It can be defined in programming languages as well as on a database level. The varchar field can be any length between zero and the declared maximum field length.
The char value's storage capacity is equal to the column's maximum size. The varchar value's storage capacity is equal to the length of the data entered, not the column's maximum size. When the length of the variable is known, char should be used. Varchar should only be used when the variable's length is unknown.
The varchar keyword is used to declare a variable character. Varchar uses variable space, which means it will only consume as many bytes as the number of characters. It helps to avoid wasting space because it just uses the space required for the string's size. Any surplus space in the database is immediately eliminated in various programming languages and database systems.
If you declare a variable of type varchar (9), for example, it will take the same number of bytes as the number of characters. So, if you're storing one character, it'll take one byte, and if you're storing nine characters, it'll take nine bytes, eliminating database space waste.
It's a SQL datatype for storing character strings with a variable-length but a maximum length specified. If the length of the string is less than the set or fixed length, it will be stored as-is, with no further blank spaces appended. The VARCHAR datatype's storage size is equal to the length of the supplied string in bytes. When the data values in a column are expected to be of variable length, we should use this datatype.
Main Differences Between Char And Varchar in Points
- Though both are SQL codes, they are very different since 'char' is used to store fixed-length characters, and 'varchar' is used to store variable-length characters.
- The letters 'char' and 'varchar' stand for character and variable character, respectively. As a result, we may deduce what they are employed for based on their abbreviations.
- The storage capacity of char is equal to the column's storage size, and it only holds items of fixed length, such as phone numbers. Varchar's storage size is determined by the string being stored, as it holds various alphanumeric strings such as an address.
- Static memory allocation is used by Char, but dynamic memory allocation is used by Varchar.
- For character storage, Char employs one byte per character. Varchar, like char, stores each character in a single byte. The distinction between them is that varchar utilizes an extra 1 or 2 bytes to store length information, whereas char does not.
- Because char is only used for fixed values, its maximum character limit is only 255. They only employ data of the string type. Varchar, on the other hand, has a character limit of 65535 characters since it can store several strings of data, and the limit is determined by the length of each string.
- The two codes are also used in distinct ways. When the length of the data value is known, programmers use char, but varchar is used when the length of data values varies for each cell.
- Char stores only certain string characters, as the name implies. Varchar, on the other hand, can store a variety of string characters such as alphabets, numerals, and variables. As a result, they're both used for different things.
- 'Char' is a fixed-length data type for storing fixed-length character string values, whereas 'Varchar' is a variable-length data type for storing variable-length alphanumeric data.
- The maximum size of this column that you declare when establishing the table is equal to the storage size of the character value. The varchar value's storage size, on the other hand, is the actual length of the data entered, not the column's maximum capacity.
- When the data entries in a column are intended to be the same size, you can use char; when the data entries in a column are expected to vary in size, you can use varchar.
- Static memory allocation is used by Char, while dynamic memory allocation is used by Varchar.
- A char variable's length can range from 0 to 255, while a varchar variable's length can range from 0 to 65,535.
- Data entries in char, which is used to store data like phone numbers, are consistent, however, data entries in varchar, which is used to store variable data like addresses, are not.
Conclusion
With computer language comes a plethora of data kinds and codes that cater to the most basic needs of consumers and programmers. SQL is one such language, and the data types 'char' and 'varchar' are similar. The data type 'Char' store's fixed-length data values with a storage size equal to the column's storage size. They're mainly utilized by programmers when they need to store data in a specific range or with short data characters. Because they are non-Unicode data types, they have a character limit of 250. Another data type that saves characters is 'varchar,' which, unlike char, may store alphanumeric or string characters. They're employed when the data values aren't constant and are constantly changing. Because they store distinct strings, they have a maximum limit of 65535 characters. Even though they both store characters, programmers use them in various ways because they have varied storage sizes and store distinct types of characters. Furthermore, char stores only fixed-length data values, whereas varchar stores data values of variable length.
