Binary string operands

Binary strings are compatible only with other binary strings. Other data types can be treated as a binary-string data type by using the BINARY, VARBINARY, or BLOB scalar functions to cast the data type to a binary string.

If one operand column is... And the other operand is... The data type of the result column is...
BINARY(x) BINARY(y) BINARY(z) where z = max(x,y)
VARBINARY(x) VARBINARY(y) or BINARY(y) VARBINARY(z) where z = max(x,y)
BLOB(x) BLOB(y) or VARBINARY(y) or BINARY(y) BLOB(z) where z = max(x,y)