How the BIT_LENGTH() function works in Mariadb?

The BIT_LENGTH() function is a string function that returns the length of a given string in bits.

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The BIT_LENGTH() function is a string function that returns the length of a given string in bits. The BIT_LENGTH() function can be used to get the number of bits that are required to store a string, such as a column, a literal value, or a function call. For example, the BIT_LENGTH() function can be used to get the length of the string ‘A’ in bits, which is 8.

Syntax

The syntax of the BIT_LENGTH() function is as follows:

BIT_LENGTH(string)

The string parameter can be any valid string expression, such as a column name, a literal value, or a function call. The string parameter is the string that you want to get the length of in bits. The string parameter cannot be NULL.

The BIT_LENGTH() function returns a numeric value, which is the length of the input string in bits. If the input string is NULL, the BIT_LENGTH() function returns NULL.

Examples

Here are some examples of using the BIT_LENGTH() function in Mariadb:

Example 1: Length of a literal string in bits

To get the length of a literal string in bits, you can simply pass the string as the parameter. For example:

SELECT BIT_LENGTH('A') AS result;

This statement returns 8 as the output, which is the length of the string ‘A’ in bits.

Example 2: Length of a column value in bits

To get the length of a column value in bits, you can use the column name as the parameter. For example, suppose you have a table called users that stores the username and the password of different users. You can use the BIT_LENGTH() function to get the length of the password column in bits for each user. For example:

SELECT username, BIT_LENGTH(password) AS result
FROM users;

This statement returns the username and the length of the password in bits for each row in the users table. For example, if the table contains the following data:

username password
Alice abc123
Bob xyz789
Charlie pqr456

The statement returns the following output:

username result
Alice 48
Bob 48
Charlie 48

Example 3: Length of a function call in bits

To get the length of a function call in bits, you can use the function call as the parameter. For example, you can use the BIT_LENGTH() function to get the length of the string that is returned by another string function. For example:

SELECT BIT_LENGTH(UPPER('a')) AS result;

This statement returns 8 as the output, which is the length of the string ‘A’, which is the upper case of the string ‘a’.

Example 4: Length of a NULL value in bits

To get the length of a NULL value in bits, you can use the NULL value as the parameter. However, the BIT_LENGTH() function will return NULL as the output, because the input value is NULL. For example:

SELECT BIT_LENGTH(NULL) AS result;

This statement returns NULL as the output, because the input value is NULL.

Some of the functions that are related to the BIT_LENGTH() function are:

  • The CHAR_LENGTH() function, which returns the length of a given string in characters. The CHAR_LENGTH() function can be used to get the number of characters that are in a string, such as a column, a literal value, or a function call. For example, the CHAR_LENGTH() function can be used to get the length of the string ‘A’ in characters, which is 1.
  • The LENGTH() function, which returns the length of a given string in bytes. The LENGTH() function can be used to get the number of bytes that are required to store a string, such as a column, a literal value, or a function call. For example, the LENGTH() function can be used to get the length of the string ‘A’ in bytes, which is 1.
  • The OCTET_LENGTH() function, which returns the length of a given string in octets. The OCTET_LENGTH() function can be used to get the number of octets that are required to store a string, such as a column, a literal value, or a function call. For example, the OCTET_LENGTH() function can be used to get the length of the string ‘A’ in octets, which is 1.

Conclusion

The BIT_LENGTH() function is a useful function that can help you get the length of a given string in bits in Mariadb. You can use it with any valid string expression, such as a column name, a literal value, or a function call. The BIT_LENGTH() function returns a numeric value, which is the length of the input string in bits. You can also use some other functions that are related to the BIT_LENGTH() function, such as the CHAR_LENGTH(), LENGTH(), and OCTET_LENGTH() functions.