How to count the number of bits of a giving string using the BIT_LENGTH() function?

BIT_LENGTH(string) is a MySQL built-in function that returns the number of Bits of a giving string. For example:

SELECT BIT_LENGTH('O'), BIT_LENGTH('©'), BIT_LENGTH('😋');
  -- +-----------------+------------------+--------------------+
  -- | BIT_LENGTH('O') | BIT_LENGTH('©')  | BIT_LENGTH('😋')     |
  -- +-----------------+------------------+--------------------+
  -- |               8 |               16 |                 32 |
  -- +-----------------+------------------+--------------------+

Reference information of the LENGTH() function:

BIT_LENGTH(str): num
  Returns the length of the string str in bits.

Arguments, return value and availability:
  str: Required. The given string to count the number of bits for.
  num: Return value. The number of bits in the given string.
  Available since MySQL 5.7.

Related MySQL functions:

• CHARACTER_LENGTH() - Number of Characters
• CHAR_LENGTH() - Number of Characters
• LENGTH() - Number of Bytes in String

⇒ CHAR() - Building String from Byte Values

⇐ ASCII() - ASCII Value of First Character

⇑ MySQL Functions on Character String Values

⇑⇑ MySQL Function References