How to convert an integer to a binary string using the BIN() function?

BIN(int) is a MySQL built-in function that converts an integer to binary string. For example:

SELECT BIN(1), BIN(2), BIN(4), BIN(8), BIN(16), BIN(1024);
  -- +--------+--------+--------+--------+---------+-------------+
  -- | BIN(1) | BIN(2) | BIN(4) | BIN(8) | BIN(16) | BIN(1024)   |
  -- +--------+--------+--------+--------+---------+-------------+
  -- | 1      | 10     | 100    | 1000   | 10000   | 10000000000 |
  -- +--------+--------+--------+--------+---------+-------------+

SELECT BIN(x'ff'), BIN(x'ffff'), BIN(x'ffffffff');
  -- +------------+------------------+----------------------------------+
  -- | BIN(x'ff') | BIN(x'ffff')     | BIN(x'ffffffff')                 |
  -- +------------+------------------+----------------------------------+
  -- | 11111111   | 1111111111111111 | 11111111111111111111111111111111 |
  -- +------------+------------------+----------------------------------+

If the input is not an integer, BIN() will try to cast it to an integer first. For example:

SELECT BIN(3.14), BIN(8.8), BIN('8.8'), BIN('1024 Bytes');
  -- +-----------+----------+------------+-------------------+
  -- | BIN(3.14) | BIN(8.8) | BIN('8.8') | BIN('1024 Bytes') |
  -- +-----------+----------+------------+-------------------+
  -- | 11        | 1000     | 1000       | 10000000000       |
  -- +-----------+----------+------------+-------------------+

SELECT BIN(TRUE), BIN(FALSE), BIN(NULL);
  -- +-----------+------------+-----------+
  -- | BIN(TRUE) | BIN(FALSE) | BIN(NULL) |
  -- +-----------+------------+-----------+
  -- | 1         | 0          | NULL      |
  -- +-----------+------------+-----------+

If you want to convert an integer from a binary string to decimal string, you need to use the CONV(str, 2, 10) function. For example:

SELECT BIN(1024), CONV('10000000000', 2, 10);
  -- +-------------+----------------------------+
  -- | BIN(1024)   | CONV('10000000000', 2, 10) |
  -- +-------------+----------------------------+
  -- | 10000000000 | 1024                       |
  -- +-------------+----------------------------+

Reference information of the BIN() function:

BIN(int): str
  Returns the binary representation of a given integer.

Arguments, return value and availability:
  int: Required. The integer to be converted.
  str: Return value. The converted binary string.
  Available since MySQL 4.0.

Related MySQL functions:

• BIN() - Converting Integer to Binary String
• CONV() - Number Base Conversion

⇒ BIT_COUNT() - Counting '1' in Binary String

⇐ ATAN2() - 2-Argument Arctangent

⇑ MySQL Functions on Numeric Values

⇑⇑ MySQL Function References