回答編集履歴
1
調整
test
CHANGED
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@@ -17,3 +17,67 @@
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order by id
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```
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# sample
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- 元データ
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```SQL
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create table tbl(
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id int primary key,
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sei varchar(100) null,
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mei varchar(100) null
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);
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insert into tbl (id, sei, mei) VALUE
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(1, '田中', '二郎'),
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(2, '田中', '二郎2'),
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(3, '田中', '二郎3'),
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(4, '田中', '二郎4'),
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(5, '高橋', '太郎'),
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(6, '高橋', '太郎2'),
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(7, '高橋', '太郎3'),
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(8, '高橋', '太郎4'),
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(9, '斎藤2', '一郎9'),
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(10, '斎藤2', '一郎'),
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(11, '斎藤2', '一郎2'),
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(12, '斎藤2', '一郎3'),
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(13, '斎藤2', '一'),
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(14, '斎藤2', '一二三'),
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(15, '斎藤2', '二郎');
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70
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```
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- 抽出
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```
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select min(id) as id,concat(sei,substr(mei,1,1)) as fullname,count(*) as cnt from tbl
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78
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group by fullname
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order by id
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```
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