将整数连接成二进制字符串并返回

Question

我想以二进制字符串的形式存储20个字节，它们来自应用程序的整数。这是我能做的最好的。两个字节只是为了使其更简单。

create table t (bs binary(2)); 

insert into t (bs) values 
(concat(unhex(hex(240)), unhex(hex(40)))) 
; 

select 
    conv(hex(left(bs, 1)), 16, 10) n1, 
    conv(hex(mid(bs, 2, 1)), 16, 10) n2 
from t; 
+------+------+ 
| n1 | n2 | 
+------+------+ 
| 240 | 40 | 
+------+------+ 

有什么不太详细的？如果不是这些功能将如何做这些转换？

Answer 1

功能来连接整数转换成二进制字符串：

create function concat_integers_into_binary(
    i1 integer, i2 integer 
) returns binary(2) deterministic 
return concat(unhex(hex(i1)), unhex(hex(i2))) 

insert into t (bs) values 
(concat_integers_into_binary(240, 40)) 

函数从二进制字符串转换为整数：

create function binary2integer(
    bs varbinary(20), position integer 
) returns integer deterministic 
return conv(hex(substring(bs, position, 1)), 16, 10) 

select 
    binary2integer(bs, 1) n1, 
    binary2integer(bs, 2) n2 
from t; 
+------+------+ 
| n1 | n2 | 
+------+------+ 
| 240 | 40 | 
+------+------+