Database design for eCommerce website with multiple products having huge specifications index
You could have a basic product table, then also a table to store different types of specs, then another table to store the specs themselves:


products
--------
  id
  name
  (a few other necessary fields)

product_spec_types
------------------
  id
  name

product_spec_values
-------------------
  id
  product_id (FK to product.id)
  spec_id (FK to product_spec_types.id)
  value


So you could have data that looks like this:


product
ID  |   NAME
----|-----------
1   |   TV
2   | kids boots

product_spec_types
ID  |  name
------------------
1   | refresh rate
2   | size (diagonal)
3   | shoe size
4   | colour

product_spec_values
ID  | Product_ID   | Spec_ID  | Value
-------------------------------------
1   | 1            | 1        | 60 HZ
2   | 1            | 2        | 32 inches
3   | 2            | 3        | 4
4   | 2            | 4        | blue w/grey



This is a very simple implementation of the Entity-Attribute-Value pattern. You could go further if you want, and add data type restrictions (such as numeric, alpha-numeric, enumerations, etc...) to product_spec_types

The main benefit of this approach is that it can be extrmemely flexible.

The downside of this approach is that it is not always fast for searching, since all attributes for all products are in one table. Sometimes it is better to create separate tables that your user's searches will run off of, and those tables will have real columns for all the attributes you want them to be able to search.