this.joinType = joinType ;
if ( joinType == JoinType.LEFT )
{
// If a left join, the RHS may be null.
idScope = new Scope2(left.getIdScope(), new ScopeOptional(right.getIdScope())) ;
nodeScope = new Scope2(left.getNodeScope(), new ScopeOptional(right.getNodeScope())) ;
}
else
{
idScope = new Scope2(left.getIdScope(), right.getIdScope()) ;
nodeScope = new Scope2(left.getNodeScope(), right.getNodeScope()) ;
}
}