Here in relation for relationship R . b3 from E2 is not related to anyone in E1 similarly a3 from E1 is not related to anyone in E3 , So they are not present in relation of R.
1) So that means when we are creating new relation for relationship , we only include entities which are participants of relationship only ?? Means there will be no NULL entries in separate relation for any relationship ??
2) Is creating New relation for Relationship like for M:N , is different from merging two relations because in merging entires for all entities will be included whether they are participant of relationship or not , Thats y they have NULL entries ??