SQL & PL/SQL

I have used the below script to create my fast refresh mv. do i need to capture rowid's for sure or i am going wrong in creating the below mv.

ALTER TABLE si_users_t

ADD CONSTRAINT user_id_pk PRIMARY KEY(user_id);

ALTER TABLE si_org_roles

ADD CONSTRAINT org_role_id_pk PRIMARY KEY(org_role_id);

ALTER TABLE si_user_org_roles

ADD CONSTRAINT org_role_user_id_pk PRIMARY KEY(org_role_id,user_id);

ALTER TABLE si_role_activities

ADD CONSTRAINT act_role_id_pk PRIMARY KEY(activity_id,role_id);

ALTER TABLE si_activities_t

ADD CONSTRAINT activity_id_pk PRIMARY KEY(activity_id);

ALTER TABLE si_org_entities_t

ADD CONSTRAINT org_entity_id_pk PRIMARY KEY(org_entity_id);

ALTER TABLE si_roles_t

ADD CONSTRAINT role_id_pk PRIMARY KEY(role_id);

CREATE MATERIALIZED VIEW LOG ON si_org_roles        WITH PRIMARY KEY,SEQUENCE INCLUDING NEW VALUES;

CREATE MATERIALIZED VIEW LOG ON si_users_t           WITH PRIMARY KEY,SEQUENCE INCLUDING NEW VALUES;

CREATE MATERIALIZED VIEW LOG ON si_user_org_roles   WITH PRIMARY KEY,SEQUENCE INCLUDING NEW VALUES;

CREATE MATERIALIZED VIEW LOG ON si_role_activities  WITH PRIMARY KEY,SEQUENCE INCLUDING NEW VALUES;

CREATE MATERIALIZED VIEW LOG ON si_activities_t     WITH PRIMARY KEY,SEQUENCE INCLUDING NEW VALUES;

CREATE MATERIALIZED VIEW LOG ON si_org_entities_t   WITH PRIMARY KEY,SEQUENCE INCLUDING NEW VALUES;

CREATE MATERIALIZED VIEW LOG ON si_roles_t         WITH PRIMARY KEY,SEQUENCE INCLUDING NEW VALUES;

CREATE MATERIALIZED VIEW MS_APPS_USER_ORG_ACTVITIES_MV

BUILD IMMEDIATE

REFRESH FAST

ON DEMAND

WITH PRIMARY KEY

AS

SELECT 

      users.user_name        user_name

     ,users.user_id          user_id

     ,act.activity_name      activity_name

     ,act.activity_id        activity_id

     ,orgs.org_entity_name   org_entity_name

     ,orgs.org_entity_id     org_entity_id

     ,roles.role_id          role_id

     ,roles.role_name        role_name

FROM si_users_t users,

     si_user_org_roles usr_org_roles,

     si_org_roles org_roles,

     si_role_activities role_act,

     si_activities_t act,

    si_org_entities_t orgs,

    si_roles_t roles

WHERE users.user_id = usr_org_roles.user_id

  AND usr_org_roles.org_role_id      = org_roles.org_role_id

  AND role_act.role_id               = org_roles.role_id

  AND role_act.activity_id           = act.activity_id

  AND orgs.org_entity_id             = org_roles.org_entity_id

  AND roles.role_id                  = org_roles.role_id;

and i come across

ORA-12052: cannot fast refresh materialized view SG61SP5PLAB.MS_APPS_USER_ORG_ACTVITIES_MV

12052. 00000 -  "cannot fast refresh materialized view %s.%s"

*Cause:    Either ROWIDs of certain tables were missing in the definition or

           the inner table of an outer join did not have UNIQUE constraints on

           join columns.

*Action:   Specify the FORCE or COMPLETE option. If this error is got

           during creation, the materialized view definition may have be

           changed. Refer to the documentation on materialized views.