Searching atributes

[vojtechjan]

It sounds like you need to modify/add to the advanced search SQL query. Do you have an example of what you are trying to achieve?

Well basically I like to search all products that have such attribute value.
For example : There some products that have ReadOnly numerical attribute "volume of the tank" with values 100(...)200(...) and so. I want to add possiblity of searching it in "advanced" search form just like price.
Also I would like to add other search option for other ReadOnly attrbutes like "propulsion type" with dropdown list that have all values of attribute listed in it.

I want to fillter out products that do not have atributes and values of them that client is searching for. I havent seen such thing anywhere else so I am just asking here if this is even possible.
Have anyone made such thing before or have any kind of hint how I can do that with attrbutes?

Many thanks