Dynamic datastructure of objects

[lumirb]

Hello,

I would like to disccuss with the following issue:
We want to create database in which we can dynamically add attributes.
The problem is, we do not know the datastructure before. The datastructure has to be defined in some metadata structure.

Example:
OBJECT-->ATTRIBUTES

My suggestion:

OBJECT_META.ID<--OBJECT_ATTRS_META.META_ID

OBJECT_META.ID<--OBJECT_DATA.META_ID
OBJECT_DATA.ID<--OBJECT_DATA_ATTRS.DATA_ID
OBJECT_ATTRS_META.META_ID<--OBJECT_DATA_ATTRS.META_ID

If I do it this way then I cannot imagine, how the response time of SQL statements will look like...

The DATA Tables should have more then 50.000.000 records!

Do you have another idea or experince?

Thank you,

LumirB

PS: I hope you can understand my problem...