two method of left out join -- more than two table;
one
select A.NAME_1,B.NAME_2,C.NAME_3 from A left join B on A.ID=B.ID left join C on B.ID_1= C.ID_1;
two
select P.NAME_1,P.NAME_2,C.NAME_3 from (select A.NAME_1,B.NAME_2,B.ID_1 from A left join B on A.ID=B.ID) P left join C on P.ID_1= C.ID_1;
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