質問編集履歴
1
多対多の関係、詳細
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@@ -115,3 +115,39 @@
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MySQL
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---
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[追記]
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多対多の結合に関して、次のようなJOIN句を入れています。
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```sql
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SELECT t1.id AS id, t1.name AS name, tags.name AS tag
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FROM t1
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LEFT JOIN tag_relation ON t1.id = tag_relation.t1_id
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LEFT JOIN tags ON tag_relation.tag_id = tags.id
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ORDER BY t1.id ASC
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LIMIT 3
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```
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テーブルとカラム
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|t1|tag_relation|tags|
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|:--|:--:|--:|
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|id|id|id|
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|name|t1_id|name|
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||tag_id||
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