求数据库加密技术方面的书

Question

同标题，最近做sql，为了安全，想做加密，求书籍及相关资料，谢谢！

Answer 1

create or replace function encrypt(inpass in varchar2)--加密的函数
return varchar2 as
string_in varchar2(78);
string_out varchar2(39);
offset number;
outpass varchar2(30);
begin
offset := mod(to_number(to_char(sysdate,'ss')),39);
string_in := 'YN8K1JOZVURB3MDETS5GPL27AXWIHQ94C6F0#$_';
string_out :='_$#ABCDEFGHIJKMNOPQRSTUVWXYZ0123456789';
outpass := substr(string_in,offset,1);
string_in := string_in||string_in;
string_in := substr(string_in,offset,39);
outpass := outpass||translate(upper(inpass),string_in,string_out);
return outpass;
end;

declare
x varchar2(50);
begin
X:=encrypt('HELLO');
DBMS_OUTPUT.put_line(X);
end;

create or replace function decrypt(outpass in varchar2)--解密的函数
return varchar2
as
string_in varchar2(78);
string_out varchar2(39);
offset number;
inpass varchar2(30);
begin
string_in := 'YN8K1JOZVURB3MDETS5GPL27AXWIHQ94C6F0#$_';
string_out :='_$#ABCDEFGHIJKMNOPQRSTUVWXYZ0123456789';
offset:=instr(string_in,substr(outpass,1,1));
string_in:=string_in||string_in;
string_in:=substr(string_in,offset,39);
inpass:=translate(upper(substr(outpass,2)),string_out,string_in);
return inpass;
end;