回答編集履歴
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sample
test
CHANGED
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@@ -13,3 +13,43 @@
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またt_user.id∋(∈)t_statas.user_idなのかによっても
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いまのSQL文で必要十分なのか微妙です
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# sample
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sample付けときます
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- 元データ
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```SQL
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create table t_user (id int not null primary key,uname varchar(30));
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insert into t_user values(1,'坂本'),(2,'阿部'),(3,'マギー');
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create table t_status(id int not null primary key,user_id int,sname varchar(30));
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insert into t_status values(1,1,'ショート'),(2,2,'キャッチャー'),(3,2,'ファースト'),(4,2,'代打'),(5,3,'サード'),(6,3,'代打');
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```
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- 検索
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```SQL
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select * from t_user as A
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left join t_status as B on A.id=B.user_id
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and B.id in(select max(id) from t_status group by user_id);
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```
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