Encryption/ Date validation

[linuxnewb]

1.
Is there a way to encrpt data (ie. a credit card number or personal information) and then retrieve it from the database later using a SELECT Statement. I am trying to get away from:

Insert into saiddatabase values password(something);
select * from saiddatabase where creditcardnum = password(something);

Any suggestions?

2.
I want to be able to verify the date entered is a valid date.
Any suggestions?

Thank you.

[Weedpacket]

1) If you're doing this to avoid work, then you should realise that you'll actually have to do more for reversible encryption - assuming you actually want real encryption and not some toy. If you want to do this because you want access to the actual data (instead of just comparing it to supplied data) then consider that you're also making it easier for the data to be retrieved illicitly - but that could be said of pretty much anything (if you can do it, then someone else sufficiently skilled/persistent/motivated can do it as well). Maybe your DBMS has some facilities for reversible encryption; PHP has the [man]mcrypt[/man] extension.
2) [man]checkdate[/man]