encoding & decoding question

[aopen]

I use mysql version 3.23.58.
I want to use 'decode' and 'encode' functions:
http://dev.mysql.com/doc/mysql/en/Encryption_functions.html

Using password I can decode and encode data in mysql.

Below is my queries that return nothing:
#1 create table.
#2 insert data using encode function
#3 trying to select data from database using decode function

Return nothing.

Why the last query returns nothing?

mysql> create table t (a blob, b int(10));
Query OK, 0 rows affected (0.00 sec)

mysql> insert into t values (encode('test','mypass'),121);
Query OK, 1 row affected (0.00 sec)

mysql> select * from t;
+------+------+
| a | b |
+------+------+
| ÂYd | 121 |
+------+------+
1 row in set (0.00 sec)

mysql> select * from t where a = decode('ÂYd','mypass');
Empty set (0.00 sec)

[TheWiz]

An encryption routine takes a 'human' value and converts it to something that is only relevant to the machine. It will have a display value, as the 'ÂYd' in your SQL output, but that value has no meaning for you, or anyone else. That's the whole point.

To use it you either use the encode() function on the entered value, or the decode() function on the database value, in order to do a comparison:

select b from t where a = encode('test','mypass');

or

select b from t where decode(a,'mypass') = 'test';

The first version is probably preferable, because you are not exposing the actual stored. You probably don't want the encrypted value returned in your select statement.

[aopen]

I can get b value from database without decoding it . Field a is only encoded.

But I want to get field 'a' from the field using my password.

select a from t where a = encode('test','mypass');

this query returns nothing.

Here what I want to acheive:
A don't want to store sensetive information in text format. That's why I'm using encoding and decoding function.

So I can put information in database using password and access the information using password.

md5 function in mysql works in one way. Just store information in database inmd5 format. But I cannot get the information.

That's why I'm using encode and decode. Maybe I'm doing something wrong.

Thanks