Disconnecting a Many to Many Relation in Prisma - many-to-many

So, I asked this question yesterday and a user on here was kind enough to point me in the right direction when using explicit many-to-many relations in Prisma.
From that accepted answer I was able to update the relation using the Connect API.
prisma.group.update({
where: {
id: groupId,
},
data: {
users: { create: { user: { connect: { id: userId } } } },
},
include: { users: true },
});
There was a slight issue with the implementation when connecting the relations in a loop, but I corrected that and made an edit to update the accepted answer with the correct code as shown below:
prisma.group.update({
where: {
id: groupId,
},
data: {
users: {
create: users.map((user) => ({
user: { connect: { id: user.id } },
})),
},
},
include: { users: true },
});
What I can't seem to figure out now is how I do the reverse and 'disconnect' the relation in a similar way. I'd be grateful for some help on this.
I've tried something like the following that I thought might work:
prisma.group.update({
where: {
id: groupId,
},
data: {
users: {
delete: users.map((user) => ({
user: { disconnect: { id: user.id } },
})),
},
},
include: { users: true },
});

With explicit many-to-many relation you can just delete from the table that represents the relation (i.e. UsersGroups in your case):
prisma.usersGroups.delete({
where: { userId_groupId: { groupId: groupId, userId: userId } },
});
If you want to delete multiple users from a group:
prisma.usersGroups.deleteMany({
where: { groupId: groupId, userId: { in: users.map((user) => user.id) } },
});

Related

is it possible to user `where` and `count` to return the count for a specified field?

I am trying to use Prisma to return a count for a boolean field where it equals 'true'.
To give some context, on the frontend I am trying to calculate the workouts that have been completed by a user as a percentage, so ideally I would like prisma to return a count for the total workouts (which I have successfully done) and the count for the userWorkouts where 'isCompleted' equal true (which I am unable to achieve), currently the count is returning all userWorkouts not just the completed ones.
Here is my current Prisma Query:
const response = await prisma.user.findUnique({
where: {
id: 1,
},
select: {
id: true,
programs: {
select: {
program: {
select: {
name: true,
blocks: {
select: {
id: true,
name: true,
week: {
select: {
id: true,
number: true,
workouts: {
select: {
userWorkouts: {
where: {
isCompleted: true,
},
},
_count: {
select: {
userWorkouts: true,
},
},
},
},
_count: {
select: {
workouts: true,
},
},
},
},
},
},
},
},
},
},
},
});
res.json(response);
};
Is this possible to achieve using Primsa? Or should I just return all userWorkouts and filter for isCompleted: true on the frontend?
I have spoken with the Prisma team and this can't be achieved yet, although there is a feature request open for it.
https://github.com/prisma/prisma/issues/8413
If you would like to help get this feature added please add you +1 to the feature request.

Sequelize 'where' on parent and child when parent hasMany childs

I have 2 models:
class User extends Model {
static associate(models) {
User.hasMany(models.Role, {
foreignKey: 'userId'
});
}
};
User.init({
firstname: {
type: DataTypes.STRING,
},
lastname: {
type: DataTypes.STRING,
},
allowedApps: {
type: DataTypes.ENUM({
values: Object.keys(PORTALS)
}),
allowNull: false
}
}, {
sequelize,
paranoid: true,
modelName: 'User',
});
class Role extends Model {
static associate(models) {
Role.BelongsTo(models.User, {
foreignKey: 'userId'
});
}
};
Role.init({
type: {
type: DataTypes.STRING,
unique: true
},
name: DataTypes.STRING,
userId: {
type: DataTypes.INTEGER,
allowNull: false,
}
}, {
sequelize,
paranoid: true,
modelName: 'Role',
});
I would like to get all users where the firstname OR the role type matches a certain condition. Something like:
User
.findAndCountAll({
where: {
$or: [
{
firstname: "John Doe"
},
{
"$Role.type$": "Admin"
}
]
},
include: [{
model: Role,
}],
}).limit=10,offset=0
.then(users => res.status(200).send(users))
.catch(error => {
return res.sendStatus(500);
});
above query giving me error: "SequelizeDatabaseError: Unknown column 'Role.type' in 'field list'"
I want to search through child model when it has one to many relationship having my limit and offset intact.Same query would give me success if user would have HasOne relation with role.
This is just an example code of what I try to achieve so please ignore any typos and silly mistakes.
After some digging:
await User.findAll({
where: {
$or: [
{
firstname: "John Doe"
},
{
"$Role.type$": "Admin"
}
]
},
include: {
model: Role,
as: 'Role',
required: false
}
});
However, it doesn't make logical sense to select Users that have no associated Role (required: false), while querying such Users with a property that exists on Role ($or: $Role.type$). If we set Required = true, then we violate your initial condition
firstname OR the role type matches a certain condition.
The following addresses this problem:
await User.findAll({
include: {
model: Role,
required: false
}
})
.then(
users => users
.filter(user => user?.firstName === "John Doe" || user.role?.type ===
"Admin");
);

How to use findAll with associations in Sequelize

I'm having problems to use the findAll() method with associations from Sequelize.
I have two models: Posts and Authors (an author has many posts and one post has one author), that I have created with Sequelize-cli and then through the migration command npx sequelize db migrate:all i have created them in mysql. To keep things organized, I have the associations between the models in another migration file (created with npx sequelize init:migrations, after all the models already existent), so my code looks like this:
AUTHOR MODEL
'use strict';
module.exports = (sequelize, DataTypes) => {
const Author = sequelize.define('Author', {
authorName: {
type: DataTypes.STRING,
validate: {
is: ["^[a-z]+$",'i'],
}
},
biography: {
type: DataTypes.TEXT,
validate: {
notEmpty: true,
}
}
}, {});
Author.associate = function(models) {
Author.hasMany(models.Post);
};
return Author;
};
POST MODEL
'use strict';
module.exports = (sequelize, DataTypes) => {
const Post = sequelize.define('Post', {
title: {
type: DataTypes.STRING,
validate: {
is: ["^[a-z]+$",'i'],
notEmpty: true,
},
},
content: {
type: DataTypes.TEXT,
validate: {
notEmpty: true,
},
},
likes: {
type: DataTypes.INTEGER,
defaultValue: 0,
validate: {
isInt: true,
},
},
}, {});
Post.associate = function(models) {
// associations can be defined here
};
return Post;
};
ASSOCIATIONS FILE (MIGRATION) (showing only parts that matter)
up: (queryInterface, Sequelize) => {
return queryInterface.sequelize.transaction(t => {
return Promise.all([
queryInterface.addColumn('Posts','AuthorId', {
type: Sequelize.INTEGER,
references: {
model: 'Authors',
key: 'id',
},
onUpdate: 'CASCADE',
onDelete: 'SET NULL',
}, { transaction: t }),
queryInterface.addColumn('Posts', 'ImagesId', {
type: Sequelize.INTEGER,
references: {
model: 'Images',
key: 'id',
},
onUpdate: 'CASCADE',
onDelete: 'SET NULL',
}, { transaction: t }),
queryInterface.addColumn('Posts', 'CategoryId', {
type: Sequelize.INTEGER,
references: {
model: 'Categories',
key: 'id',
},
onUpdate: 'CASCADE',
onDelete: 'SET NULL',
}, { transaction: t }),
]);
});
This is working fine apparently, since in Mysql-Workbench it shows me the following:
But, when I try to use the findAll() like this:
const { Post, Author } = require('../models/index');
function(response) {
Post.findAll({
attributes: ['id', 'title', 'content', 'likes'],
include: {
model: Author,
}
})
.then(result => response.json(result))
.catch(error => response.send(`Error getting data. Error: ${error}`));
It gives me the following error:
SequelizeEagerLoadingError: Author is not associated to Post!
So, I dont know anymore how to proceed. I've been trying many others approaches, but all of then unsuccessfully. I read already many other questions here in StackOverFlow about how to solve this sort of problem, but those were unsuccessfully too.
Thanks in advance.
You need to define the association for Post also as you are querying upon Post model
Post.associate = function(models) {
Post.belongsTo((models.Author);
};
You need to add an association from both ends, Post -> Author and Author -> Post , this way you will never stuck in this kind of error.
Summarizing this documentation we have the following:
If you have these models:
const User = sequelize.define('user', { name: DataTypes.STRING });
const Task = sequelize.define('task', { name: DataTypes.STRING });
And they are associated like this:
User.hasMany(Task);
Task.belongsTo(User);
You can fetch them with its associated elements in these ways:
const tasks = await Task.findAll({ include: User });
Output:
[{
"name": "A Task",
"id": 1,
"userId": 1,
"user": {
"name": "John Doe",
"id": 1
}
}]
And
const users = await User.findAll({ include: Task });
Output:
[{
"name": "John Doe",
"id": 1,
"tasks": [{
"name": "A Task",
"id": 1,
"userId": 1
}]
}]

Sequelize include even if it's null

I am using Sequelize express with Node.js as the backend, some data from my sequelize I need to include to another table but some of these data is null so the whole result I’m getting is null.
Question: how can I return some data if data it's available and return the other null if not data is there
router.get("/scheduled/:id", function(req, res, next) {
models.Order.findOne({
where: {
id: req.params.id
},
attributes: ['orderStatus', 'id', 'serviceId', 'orderDescription', 'orderScheduledDate'],
include: [{
model: models.User,
attributes: ['firstName', 'phoneNumber']
}]
}).then(function(data) {
res.status(200).send({
data: data,
serviceName: data["serviceId"]
});
});
});
I want: the result should return null if there is no user for the order and return order details and user when it is null.
However, a where clause on a related model will create an inner join and return only the instances that have matching sub-models. To return all parent instances, you should add required: false for more detail check nested-eager-loading
var users = require('./database/models').user;
models.Order.findOne({
where: {
id: req.params.id
},attributes: ['orderStatus','id','serviceId','orderDescription','orderScheduledDate'],
include: [
{model: users,required: false,
attributes: ['firstName','phoneNumber']
}
]
}).then(function(data) {
res.status(200).send({data : data,serviceName : data["serviceId"]});
});
You can add attribute required: false,
const result = await company.findAndCountAll({
where: conditions,
distinct: true,
include: [
media,
{
model: tag,
where: tagCond,
},
{ model: users, where: userCond, attributes: ['id'] },
{
model: category_company,
as: 'categoryCompany',
where: categoryCond,
},
{ model: media, as: 'logoInfo' },
{ model: city, as: 'city' },
{
model: employee,
as: 'employees',
required: false,
include: [{
model: media,
as: 'avatarInfo',
}],
where: {
publish: {
[Op.ne]: -1,
},
},
},
],
order: [['createdAt', 'DESC']],
...paginate({ currentPage: page, pageSize: limit }),
});

Sequelize Query - Finding records based on many-to-many table and parent table

Given the following sequelize models:
var User = db.define('user', {
name: Sequelize.STRING
});
var Group = db.define('group', {
name: Sequelize.STRING,
public : { type: Sequelize.BOOLEAN, defaultValue: true }
});
Group.belongsToMany(User, { as: 'specialUsers', through: 'user_groups', foreignKey: 'group_id' });
User.belongsToMany(Group, { through: 'user_groups', foreignKey: 'user_id' });
How would I go about finding the Groups for a through the Groups model where the Groups returned should be those where the user has a record in the many to many table -- or -- the group is a public group?
I've tried something like this:
return Group.findAll({
attributes: ['name', 'public'],
include: [{
model: User,
as: 'specialUsers',
where: {
$or : [
{name: 'Neill'},
Sequelize.literal('"group"."public" = true')
]
}
}]
});
return Group.findAll({
attributes: ['name', 'public'],
include: [{
model: User,
as: 'specialUsers',
}],
where: {
$or : {
'$users.name$": 'Neill',
public: true
}
}
});
Should work if you are on a fairly recent version. Note that I moved the where out of the include