How to perform binary/hexadecimal string and integer conversion using the CONV() function?

CONV(N, from_base, to_base) is a MySQL built-in function that allows you to perform binary/hexadecimal string and integer conversion. For example:

SELECT CONV('FF', 16, 10), CONV('FF', 16, 2);
  -- +--------------------+-------------------+
  -- | CONV('FF', 16, 10) | CONV('FF', 16, 2) |
  -- +--------------------+-------------------+
  -- | 255                | 11111111          |
  -- +--------------------+-------------------+

SELECT CONV(255, 10, 2), CONV(255, 10, 16);
  -- +------------------+-------------------+
  -- | CONV(255, 10, 2) | CONV(255, 10, 16) |
  -- +------------------+-------------------+
  -- | 11111111         | FF                |
  -- +------------------+-------------------+

Reference information of the CONV() function:

CONV(in, from_base, to_base) : out
  Converts numbers between different number bases. Returns a string
  representation of the number N, converted from base from_base to base
  to_base. Returns NULL if any argument is NULL.

Arguments, return value and availability:
  in: Required. The input number in from_base base.
  out: Return value. The output number in to_base base.
  Available since MySQL 5.7.

⇒ ELT() - String at Given Index

⇐ CONCAT_WS() - Concatenation with Separator

⇑ MySQL Functions on Character String Values

⇑⇑ MySQL Function References