回答編集履歴
3
カラム名の修正
answer
CHANGED
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@@ -82,7 +82,7 @@
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82
82
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```SQL
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83
83
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use test;
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84
84
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85
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-
SELECT f.name, group_concat(m.name) AS
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85
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+
SELECT f.name, group_concat(m.name) AS members
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86
86
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FROM favorites AS fav
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87
87
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LEFT JOIN members AS m
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88
88
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USING (member_id)
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@@ -93,4 +93,4 @@
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93
93
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94
94
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####SELECT結果
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95
95
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96
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-
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2
整形
answer
CHANGED
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@@ -41,12 +41,12 @@
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41
41
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name varchar(255)
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42
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) ENGINE InnoDB CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
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43
43
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44
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-
create table fruits(
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44
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+
create table fruits (
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45
45
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fruit_id int PRIMARY KEY,
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46
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name varchar(255)
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47
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) ENGINE InnoDB CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
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48
48
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49
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-
create table favorites(
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49
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+
create table favorites (
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50
50
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member_id int,
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51
51
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fruit_id int,
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52
52
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PRIMARY KEY(member_id, fruit_id)
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@@ -62,7 +62,8 @@
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62
62
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```SQL
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63
63
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use test;
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64
64
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65
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-
SELECT m.name, group_concat(f.name) AS fruits
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65
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+
SELECT m.name, group_concat(f.name) AS fruits
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66
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FROM favorites AS fav
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66
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LEFT JOIN members AS m
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67
68
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USING (member_id)
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68
69
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LEFT JOIN fruits AS f
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@@ -81,7 +82,8 @@
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81
82
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```SQL
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82
83
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use test;
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83
84
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84
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-
SELECT f.name, group_concat(m.name) AS fruits
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85
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+
SELECT f.name, group_concat(m.name) AS fruits
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86
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+
FROM favorites AS fav
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85
87
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LEFT JOIN members AS m
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86
88
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USING (member_id)
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87
89
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LEFT JOIN fruits AS f
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1
別視点追加
answer
CHANGED
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@@ -74,4 +74,21 @@
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74
74
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75
75
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####SELECT結果
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76
76
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77
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-
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77
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+
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78
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+
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79
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+
####別視点
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80
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+
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81
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+
```SQL
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82
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+
use test;
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83
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+
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84
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+
SELECT f.name, group_concat(m.name) AS fruits FROM favorites AS fav
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85
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+
LEFT JOIN members AS m
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86
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+
USING (member_id)
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87
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+
LEFT JOIN fruits AS f
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88
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+
USING (fruit_id)
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89
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+
GROUP BY f.fruit_id;
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90
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+
```
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91
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+
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92
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+
####SELECT結果
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93
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+
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94
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+
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