Syntax:
~

Invert all bits.

The result type depends on whether the bit argument is evaluated as a
binary string or number:

o Binary-string evaluation occurs when the bit argument has a binary
  string type, and is not a hexadecimal literal, bit literal, or NULL
  literal. Numeric evaluation occurs otherwise, with argument
  conversion to an unsigned 64-bit integer as necessary.

o Binary-string evaluation produces a binary string of the same length
  as the bit argument. Numeric evaluation produces an unsigned 64-bit
  integer.

For more information, see the introductory discussion in this section.

URL: https://dev.mysql.com/doc/refman/8.4/en/bit-functions.html

