Performance effect on field length When we are adding a text field to a content type the default length is 255. I am curious to know the performance effect of the field types and the length have for it.

Is there a preferred order of fields and length based on performance? so that we can chose our fields accordingly.
Going over 255 means that field can not easily be indexed and thus if you filter on it in views or in a query it will be slow. As long as you stay below this limit all is well.