我有以下格式的数据库结构,数据库结构
科目表
subject_id subject_name
1 HTML
2 Java
章节表
chapter_id chapter_name subject_id
1 Doctype 1
2 Intro to Java 2
教程表
tutorial_id tutorial_name chapter_id subject_id
1 Intro to doctype 1 1
2 Details of doctype 1 1
3 Intro to JVM 2 2
应该subject_id在TU torials表?
您可以通过谷歌搜索为星型模式 –