Syntax:
<<

Shifts a longlong (BIGINT) number or binary string to the left.

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.

Bits shifted off the end of the value are lost without warning,
regardless of the argument type. In particular, if the shift count is
greater or equal to the number of bits in the bit argument, all bits in
the result are 0.

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

URL: https://dev.mysql.com/doc/refman/8.0/en/bit-functions.html

