oop - Alternate implementation of design Pattern in PHP -

this question might obvious people , solution might simple well. save hours of time.

i working on project have seen model structure shown in diagram below.

in design structure have simplerow , advancerow classes. these 2 classes implement row interface , extend rowabstract class , rowabstract class composites masterrow class.

this design seems similar strategy pattern to.

my question here design pattern this? kind of variation of strategy pattern? or practice , not design pattern?

thanks help.

the diagram here drawn reference might contain errors. please ignore them.

this looks composite pattern without recursion. if not it's random polymorphism. not has name.

http://en.wikipedia.org/wiki/composite_pattern