denormalization tables to 1NF

Question

How can denormalize this to 1NF.

    --------------------------------------------------
    |         |         |              |             |
    |         V         V              V             V
-----------------------------------------------------------
|post_id|post_title|post_text|post_submited_time|user_name|
-----------------------------------------------------------


    ------------------------------------------------
    |            |                 |               |           
    |            V                 V               V           
---------------------------------------------------------
|comment_id|comment_text|comment_submited_time|user_name|
---------------------------------------------------------

   -----------
   |         |
   |         V
--------------------
|post_id|comment_id|
--------------------

I want to one table in one normal form that when I normalize that result was up tables.

Answer 1

It depends on the database you are using, because there are databases like postgresql that can have arrays or complex dataobjects as datatype in their columns. It normally comes with a price: you can not index nor organize this data. Then might it for instance become difficult to find out which comments an user has given on which posts. If you take a look at your own Stackoverflow.com profile, then will you see the benefit of keeping this information separated.

You can remove one table however. If you create a foreign key to the post_id in the comments-table then will you have one table less in your design yet you can make use of indices just as you need.