内容简介：用时4小时，调试加数据库设置，代码编写，查文档。允许我偷个懒，不想总结了，仔细阅读内容，基本上可以了解Sequelize在联表查询上的基本用法了
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一对一
在controller里面如下写
// 获取学生信息 通过一对多的联系 async info(){ const { ctx, app } = this; let result = await app.model.Student.findAll({ include: { model: app.model.Info } }); ctx.body = result; } 复制代码获取到的值如下：
[ // 第一个学生 { "id": 1, "number": "160101", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:16:09", "updatedAt": "2019-05-12 13:16:12", "deletedAt": null, "info": { // 联表查到的信息 "sex": "男", "id": 1, "name": "许仙", "age": 23, "studentId": 1, "createdAt": "2019-05-12 13:25:58", "updatedAt": "2019-05-12 13:26:01", "deletedAt": null } }, // 第二个学生 { "id": 2, "number": "160201", "password": "202cb962ac59075b964b07152d234b70", "classId": 2, "createdAt": "2019-05-12 13:16:32", "updatedAt": "2019-05-12 13:16:35", "deletedAt": null, "info": { "sex": "女", "id": 2, "name": "白素贞", "age": 20, "studentId": 2, "createdAt": "2019-05-12 13:26:41", "updatedAt": "2019-05-12 13:26:46", "deletedAt": null } }, { "id": 3, "number": "160102", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:17:17", "updatedAt": "2019-05-12 13:17:21", "deletedAt": null, "info": { "sex": "男", "id": 3, "name": "法海", "age": 22, "studentId": 3, "createdAt": "2019-05-12 13:27:20", "updatedAt": "2019-05-12 13:27:22", "deletedAt": null } }, { "id": 4, "number": "160103", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:17:51", "updatedAt": "2019-05-12 13:17:54", "deletedAt": null, "info": { "sex": "女", "id": 4, "name": "小青", "age": 18, "studentId": 4, "createdAt": "2019-05-12 13:27:48", "updatedAt": "2019-05-12 13:27:51", "deletedAt": null } }, { "id": 5, "number": "160104", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:18:13", "updatedAt": "2019-05-12 13:18:16", "deletedAt": null, "info": { "sex": "女", "id": 5, "name": "金如意", "age": 20, "studentId": 5, "createdAt": "2019-05-12 13:28:34", "updatedAt": "2019-05-12 13:28:37", "deletedAt": null } }, { "id": 6, "number": "160202", "password": "202cb962ac59075b964b07152d234b70", "classId": 2, "createdAt": "2019-05-12 13:18:36", "updatedAt": "2019-05-12 13:18:39", "deletedAt": null, "info": { "sex": "男", "id": 6, "name": "景松", "age": 23, "studentId": 6, "createdAt": "2019-05-12 13:30:07", "updatedAt": "2019-05-12 13:30:10", "deletedAt": null } } ] 复制代码 -
一对多
// 获取班级名为 软件工程1601 的班级学生 async student(){ const { ctx, app } = this; let result = await app.model.Classes.findAll({ where: { name: '软件工程1601' }, include: { model: app.model.Student } }) ctx.body = result; } 复制代码获取数据如下：
[ { "id": 1, "name": "软件工程1601", "createdAt": "2019-05-12 13:11:43", "updatedAt": "2019-05-12 13:11:47", "deletedAt": null, "students": [ { "id": 1, "number": "160101", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:16:09", "updatedAt": "2019-05-12 13:16:12", "deletedAt": null }, { "id": 3, "number": "160102", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:17:17", "updatedAt": "2019-05-12 13:17:21", "deletedAt": null }, { "id": 4, "number": "160103", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:17:51", "updatedAt": "2019-05-12 13:17:54", "deletedAt": null }, { "id": 5, "number": "160104", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:18:13", "updatedAt": "2019-05-12 13:18:16", "deletedAt": null } ] } ] 复制代码 -
多对多
从学生获取课程信息
// 获取学生的选课内容 async lession(){ const { ctx, app } = this; let result = await app.model.Student.findAll({ where:{ id: 1, }, include: [ {model: app.model.Info}, {model: app.model.Lession} ] }); ctx.body = result; } 复制代码这里的话，注意include的值为一个数组了，这样可以多个联表获取数据
数据如下：
[ { "id": 1, "number": "160101", "password": "202cb962ac59075b964b07152d234b70", "classId": 1, "createdAt": "2019-05-12 13:16:09", "updatedAt": "2019-05-12 13:16:12", "deletedAt": null, "info": { "sex": "男", "id": 1, "name": "许仙", "age": 23, "studentId": 1, "createdAt": "2019-05-12 13:25:58", "updatedAt": "2019-05-12 13:26:01", "deletedAt": null }, "lessions": [ { "id": 1, "name": "计算机网络", "createdAt": "2019-05-12 13:12:32", "updatedAt": "2019-05-12 13:12:35", "deletedAt": null, "lession_student": { "lessionId": 1, "studentId": 1, "createdAt": "2019-05-12 13:20:35", "updatedAt": "2019-05-12 13:20:40", "deletedAt": null } }, { "id": 2, "name": "Java程序设计", "createdAt": "2019-05-12 13:12:50", "updatedAt": "2019-05-12 13:12:52", "deletedAt": null, "lession_student": { "lessionId": 2, "studentId": 1, "createdAt": "2019-05-12 13:23:10", "updatedAt": "2019-05-12 13:23:13", "deletedAt": null } }, { "id": 3, "name": "软件项目管理", "createdAt": "2019-05-12 13:13:07", "updatedAt": "2019-05-12 13:13:10", "deletedAt": null, "lession_student": { "lessionId": 3, "studentId": 1, "createdAt": "2019-05-12 13:24:21", "updatedAt": "2019-05-12 13:24:24", "deletedAt": null } } ] } ] 复制代码从课程获取选课学生：
// 获取某个课的参课学生 async lessionStudent(){ const { ctx, app } = this; let result = await app.model.Lession.findAll({ where:{ name: '网络安全' }, include: { model: app.model.Student, include: { model: app.model.Info } } }); ctx.body = result; } 复制代码这里注意，在include的下面又有一个include，第二个include是相对Student表的
数据如下：
[ { "id": 4, "name": "网络安全", "createdAt": "2019-05-12 13:13:22", "updatedAt": "2019-05-12 13:13:25", "deletedAt": null, "students": [ { "id": 2, "number": "160201", "password": "202cb962ac59075b964b07152d234b70", "classId": 2, "createdAt": "2019-05-12 13:16:32", "updatedAt": "2019-05-12 13:16:35", "deletedAt": null, "lession_student": { "lessionId": 4, "studentId": 2, "createdAt": "2019-05-12 13:24:59", "updatedAt": "2019-05-12 13:25:03", "deletedAt": null }, "info": { "sex": "女", "id": 2, "name": "白素贞", "age": 20, "studentId": 2, "createdAt": "2019-05-12 13:26:41", "updatedAt": "2019-05-12 13:26:46", "deletedAt": null } }, { "id": 6, "number": "160202", "password": "202cb962ac59075b964b07152d234b70", "classId": 2, "createdAt": "2019-05-12 13:18:36", "updatedAt": "2019-05-12 13:18:39", "deletedAt": null, "lession_student": { "lessionId": 4, "studentId": 6, "createdAt": "2019-05-12 13:25:12", "updatedAt": "2019-05-12 13:25:15", "deletedAt": null }, "info": { "sex": "男", "id": 6, "name": "景松", "age": 23, "studentId": 6, "createdAt": "2019-05-12 13:30:07", "updatedAt": "2019-05-12 13:30:10", "deletedAt": null } } ] } ] 复制代码
4. 总结
用时4小时，调试加数据库设置，代码编写，查文档。允许我偷个懒，不想总结了，仔细阅读内容，基本上可以了解Sequelize在联表查询上的基本用法了
以上所述就是小编给大家介绍的《在EggJS中使用Sequelize做联表查询》，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对 码农网 的支持！
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