Oracle database design

Question

Hi,
I am designing a database and want to design it based on 3NF. I have a table and few columns that are not a one to many relation ship. Can I design it in such a way those columns that are not a child to be in few seperate tables, with one to one relationship? Example: My main table is a program table, and I hvae few columns that are Analysis DEsc, Analysis Date and Analysis BY. I want to keep those columns in a seperate table. Please let me know how to design this?
Thanks for your time and help.

Answer 1

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LOBs are always stored at separate locations outside the table structure. The table itself holds just a reference (filepointer?) to this location.
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Always? No - that is not correct.
The default storage for LOBs is inline. Only LOBs larger than ~4000 bytes are stored out-of-line unless you specify a storage clause.
Each lob locator is about 80+ bytes and 80 bytes can be a substantial percentage of the average row length. For rows of length 400 with a lob locator you can only store fewer than 20 rows in an 8k block. Assuming you could actually store 20 rows per block then without the locator the length is 320 (20% less) so for every 5 rows you have room for a new row so could store 24 rows per block. That is 16% greater rows per block and fewer blocks that need to be manipulated to get the data you really want.
For Data Warehouse applications in particular 16% is huge savings since LOB data access is only a small fraction of the data accessed. So for those applications it is common to separate the lobs completely, almost treating them as dimension columns, and tie them to the main (fact) table by the primary key.
Even for OLTP applications LOB manipulation is often asychronous with the manipulation of the other data so it is relatively easy to create an extra table and not even have to deal with it for the main processing and queries.
See the SecureFiles and Large Objects Developer's Guide
http://docs.oracle.com/cd/B28359_01/appdev.111/b28393/adlob_tables.htm
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Inline and Out-of-Line LOB Storage
LOB columns store locators that reference the location of the actual LOB value. Depending on the column properties you specify when you create the table, and depending the size of the LOB, actual LOB values are stored either in the table row (inline) or outside of the table row (out-of-line).
LOB values are stored out-of-line when any of the following situations apply:
If you explicitly specify DISABLE STORAGE IN ROW for the LOB storage clause when you create the table.
If the size of the LOB is greater than approximately 4000 bytes (4000 minus system control information), regardless of the LOB storage properties for the column.
If you update a LOB that is stored out-of-line and the resulting LOB is less than approximately 4000 bytes, it is still stored out-of-line.
LOB values are stored inline when any of the following conditions apply:
When the size of the LOB stored in the given row is small, approximately 4000 bytes or less, and you either explicitly specify ENABLE STORAGE IN ROW or the LOB storage clause when you create the table, or when you do not specify this parameter (which is the default).
When the LOB value is NULL (regardless of the LOB storage properties for the column).
Using the default LOB storage properties (inline storage) can allow for better database performance; it avoids the overhead of creating and managing out-of-line storage for smaller LOB values. If LOB values stored in your database are frequently small in size, then using inline storage is recommended.