別の上で1つの列に優先順位を付けます

Michi :

DB-フィドル

CREATE TABLE logistics (
    id int primary key,
    campaign VARCHAR(255),
    quantity_offered VARCHAR(255),
    quantity_ordered VARCHAR(255), 
    quantity_delivered VARCHAR(255),
    quantity_recorded VARCHAR(255),
    quantity_completed VARCHAR(255)
);

INSERT INTO logistics
(id, campaign,
quantity_offered, quantity_ordered, quantity_delivered, 
quantity_recorded, quantity_completed
)
VALUES 
("1", "C001", "500", "450", "465", "462", "465"),
("2", "C002", "700", "570", NULL, NULL, NULL),
("3", "C003", "600", "610", "605", "602", NULL),
("4", "C004", "300", NULL, NULL, NULL, NULL),
("5", "C005", "400", "425", NULL, NULL, NULL),
("6", "C006", "900", "870", "868", NULL, NULL),
("7", "C007", "350", "360", "372", "375", "390"),
("8", "C008", "250", "290", NULL, NULL, NULL);

上記の表では、私は別の持っているcampaigns彼らが対応しますquantities。さまざまに充填されています。
quantitiescolumns

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今、私が取得したい、最新の利用可能量をそれぞれにcampaign次のような階層に基づきます：

quantity_completed > quantity_recorded > quantity_delivered > quantity_ordered > quantity_offered

結果は次のようになります。

Campaign      Quantity
C001            465
C002            570
C003            602
C004            300
C005            425
C006            870
C007            390
C008            290

クエリは、これを達成するために私が必要なのですか？

ゴードン・リノフ：

用途coalesce()：

select campaign, coalesce(quantity_completed, quantity_recorded, quantity_delivered, quantity_ordered, quantity_offered) as quantity
from logistics;