如何在没有额外查询的情况下删除 sequelize 中的关联？

Question

我在 exercise 和 muscle 模型之间有很多关联。我删除了单个关联

models.Exercise.find({where: {id: exerciseId}})
                .then(function(exercise){
                    exercise.removeMuscle(muscleId);
                    res.sendStatus(200);
                });

ORM 运行s 3 个查询，其中 2 个相似

Executing (default): SELECT `Muscule`.`id`, `Muscule`.`title`, `Muscule`.`description`, `Muscule`.`video`, `Muscule`.`createdAt`,
    `Muscule`.`updatedAt`, `muscle_exercise`.`createdAt` AS `muscle_exercise.createdAt`, `muscle_exercise`.`updatedAt` AS `muscle_
    exercise.updatedAt`, `muscle_exercise`.`MusculeId` AS `muscle_exercise.MusculeId`, `muscle_exercise`.`ExerciseId` AS `muscle_exercise.ExerciseId` FROM `Muscules` AS `Muscule` INNER JOIN `muscle_exercise` AS `muscle_exercise` ON `Muscule`.`id` = `muscle_exercise`.`MusculeId` AND `muscle_exercise`.`ExerciseId` = 11;



 Executing (default): SELECT `Muscule`.`id`, `Muscule`.`title`, `Muscule`.`description`, `Muscule`.`video`, `Muscule`.`createdAt`,
    `Muscule`.`updatedAt`, `muscle_exercise`.`createdAt` AS `muscle_exercise.createdAt`, `muscle_exercise`.`updatedAt` AS `muscle_
    exercise.updatedAt`, `muscle_exercise`.`MusculeId` AS `muscle_exercise.MusculeId`, `muscle_exercise`.`ExerciseId` AS `muscle_exercise.ExerciseId` FROM `Muscules` AS `Muscule` INNER JOIN `muscle_exercise` AS `muscle_exercise` ON `Muscule`.`id` = `muscle_exercise`.`MusculeId` AND `muscle_exercise`.`ExerciseId` = 11;


    Executing (default): DELETE FROM `muscle_exercise` WHERE `ExerciseId` = 11 AND `MusculeId` IN (52)

有什么办法可以避免重复查询吗？如果我可以逃避第一个和第二个查询并且运行只有第三个实际上做了一些有用的事情，那将是完美的？

Answer 1

您可以像 documentation using set function 那样传递关联对象数组而不是您尝试删除的对象。但这基本上会给您留下三个查询。

为了仅在一个 DELETE 查询中实现它，您需要在代码中添加一个关系模型。在您的情况下，它看起来像这样：

models.Exercise = sequelize.define("exercise", {
   /* attributes */
});

models.Muscle = sequelize.define("muscle", {
   /* attributes */
});

models.exercise_muscle_tie = sequelize.define("exercise_muscle_tie", {
}, {
    freezeTableName: true
});

models.Exercise.belongsToMany(models.Muscle, { as: 'muscles', foreignKey: 'exerciseId', through: models.exercise_muscle_tie });
models.Muscle.belongsToMany(models.Exercise, { as: 'exercises', foreignKey: 'muscleId', through: models.exercise_muscle_tie });

在您定义它并将其与 belongsToMany 关联到模型后，您的 删除脚本 将是：

models.exercise_muscle_tie.destroy({ where: { exerciseId: 1856, muscleId: 57344 } })

已生成 SQL:

Executing (default): 
DELETE FROM `exercise_muscle_tie` WHERE `exerciseId` = 1856 AND `muscleId` = 57344

如何在没有额外查询的情况下删除 sequelize 中的关联？

how to remove association in sequelize without extra query?

mysql

orm

node.js

sequelize.js