MySQL >选择 -> Hex(A), -> Hex(A), A=-> G; *************************** 1。行*************************** 六角(A):61 六角(A):612020 A=:1 1行集(0秒) MySQL >选择 ->进制(二进制(A)), (六->二进制(A)), ->二进制('a')=二进制('a' G); *************************** 1。行*************************** 十六进制(二进制(A)):61 十六进制(二进制(A)):612020 二进制(A)=(a):0元 1行集(0秒) For CHAR and VARCHAR, the comparison is the character value, so the return value of the first comparison is 1.For BINARY and VARBINARY, the comparison is binary, a's sixteen is 61, a's sixteen is 612020, obviously different, so second comparison return value is 0.