回答編集履歴
1
sample
test
CHANGED
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@@ -21,3 +21,39 @@
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21
21
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- class_userテーブル
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22
22
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23
23
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クラス(c_id)、出席番号(c_no)、学籍番号(u_id)
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24
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+
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25
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26
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27
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# sample
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28
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29
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30
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31
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```SQL
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32
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33
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create table user(u_id int primary key,u_name varchar(30));
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34
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35
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insert into user values(101,'青木'),(102,'井上'),(103,'上野'),(104,'江藤'),(105,'大熊');
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36
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37
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create table class(c_id int primary key,c_name varchar(30));
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38
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39
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insert into class values(1,'1年1組'),(2,'2年2組');
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40
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41
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create table class_user(c_id int,c_no int,u_id int,unique(c_id,c_no),unique(u_id));
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42
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43
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insert into class_user values(1,1,101),(1,2,102),(1,3,103),(2,1,104),(2,2,105);
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44
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45
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```
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46
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47
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48
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49
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- 一覧
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50
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51
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```SQL
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52
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53
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select * from class_user as t1
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54
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55
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inner join user as t2 on t1.u_id=t2.u_id
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56
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57
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inner join class as t3 on t1.c_id=t3.c_id
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58
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59
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```
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