回答編集履歴
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追記
test
CHANGED
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@@ -7,3 +7,59 @@
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7
7
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またtelとtimeが両方一致する場合はこれもidの逆順でしょうか？
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8
8
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9
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それともtelとtimeが両方一致するケースはないと保証されていますか？
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# sample
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とりあえずsample上げておきます。
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- 元データ
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```
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create table tbl(id int not null unique,tel varchar(20),time date,unique(tel,time));
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insert into tbl(id,tel,time) values
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(1,'08000001111','2017-07-01'),
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(2,'08011112222','2017-07-02'),
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(3,'08022223333','2017-07-03'),
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(4,'08033334444','2017-07-04'),
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(5,'08000001111','2017-07-05'),
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(6,'08055556666','2017-07-06'),
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(7,'08000001111','2017-06-30');
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```
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- 抽出
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```SQL
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select t4.id,t4.tel,t4.time from (
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select *,(select @a:=@a+1 from (select @a:=0) as dummy) as rank from tbl as t1
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where exists (select tel from tbl t2 group by tel
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having t1.tel=t2.tel and t1.time=max(t2.time) )
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order by time desc
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) as t3
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left join tbl as t4 on t3.tel=t4.tel
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order by rank,t4.time desc
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```
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