CREATE TABLE T1 (
    MASTER_ID  INTEGER NOT NULL
);

CREATE TABLE T2 (
    MASTER_ID  INTEGER NOT NULL,
    DETAIL_ID  INTEGER NOT NULL
);

ALTER TABLE T1 ADD CONSTRAINT pk_T1 PRIMARY KEY (MASTER_ID);
ALTER TABLE T2 ADD CONSTRAINT pk_T2 PRIMARY KEY (MASTER_ID, DETAIL_ID);

CREATE INDEX T2_IDX1 ON T2 (DETAIL_ID);



select *
from T1 join T2 using (MASTER_ID)
where MASTER_ID = 1   

Plan
--------------------------------------------------------------------------------
PLAN JOIN (T1 NATURAL, T2 INDEX (PK_T2))

select *
from T1 join T2 using (MASTER_ID)
where T1.MASTER_ID = 1   

Plan
--------------------------------------------------------------------------------
PLAN JOIN (T2 INDEX (PK_T2), T1 INDEX (PK_T1))

select *
from T1 join T2 using (MASTER_ID)
where T2.MASTER_ID = 1   

Plan
--------------------------------------------------------------------------------
PLAN JOIN (T2 INDEX (PK_T2), T1 INDEX (PK_T1))