回答編集履歴
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こうしｎ
test
CHANGED
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@@ -1,2 +1,47 @@
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1
1
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ソート用に国のリストをテーブルにしておくほうがよいかもしれません
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2
2
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またSQLのデータには原則順番はないため、「一番最初」を担保するなんらかのカラム（もしくは条件）が必要です
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3
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+
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4
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# 参考
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5
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```SQL
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6
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CREATE TABLE furniture (
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7
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id int primary key auto_increment,
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8
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css VARCHAR(10),
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9
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country VARCHAR(3),
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10
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number VARCHAR(15)
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);
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INSERT INTO furniture (id,css,country, number) VALUES
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(1,'Chair', 'JPN', '9P5X-8HJ5-L2QP'),
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14
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(2,'Chair', 'USA', 'A8C5-H4U6-XU2Q'),
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15
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(3,'Chair', 'KOR', 'V3J6-S5K3-U6W3'),
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16
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(4,'Table', 'JPN', 'F5P5-K6NS-8Q2Q'),
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(5,'Table', 'USA', 'G4C5-K2Q2-X9KP'),
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(6,'Table', 'FRA', 'A7C7-H5N5-L2P2'),
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19
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(7,'Sofa', 'KOR', 'O9K3-H3J3-V6N2'),
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20
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(8,'Sofa', 'USA', 'G2P3-U3H9-X3V3'),
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21
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(9,'Sofa', 'KOR', 'M6U2-V2Q2-R2Q2'),
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22
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(10,'Bed' , 'CHN' ,'A5L2-K2V6-K5K5'),
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(11,'Bed' , 'FRA' ,'G8N7-H9X5-V7P2');
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create table country(
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id int primary key,
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sort int null,
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cname varchar(20));
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create table country(
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id int primary key,
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sort int null,
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cname varchar(20));
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insert into country values
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(1,null,'CHN'),
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37
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(2,1,'JPN'),
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38
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(3,3,'KOR'),
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(4,2,'USA');
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40
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select * from furniture as t1
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left join country as t2
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44
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on t1.country=t2.cname
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45
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where not exists (select 1 from furniture where t1.country=country and t1.id>id)
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46
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order by sort is null asc ,sort asc
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47
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```
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