I have 2 models Prophet and Task and they have a m:n relationship:
Prophets
const prophet = sequelize.define('prophets', {
name: {
type: Sequelize.STRING,
primaryKey: true,
unique: true
}
});
prophet.relationship = function(task) {
prophet.belongsToMany(task, {
through: 'prophetTasks',
as: 'tasks',
foreignKey: 'prophetName'
});
};
Tasks
const task = sequelize.define('tasks', {
name: {
type: Sequelize.STRING,
primaryKey: true,
unique: true
}
});
task.relationship = function(prophet) {
task.belongsToMany(prophet, {
through: 'prophetTasks',
as: 'prophets',
foreignKey: 'taskName'
});
};
EDITED:
my problem is sometimes I have to update a prophet which might remove some relationships with tasks, but I cant figure out how to delete the tasks that have no more relationship with any prophets.
I believe I should find all tasks that doesnt belong in prophetTasks table anymore, but I dont know how to query that with sequelize
You can use ON DELETE CASCADE
So whenever the row is deleted, data containing it as a foreign key will be deleted.
Related
Edit: I have determined that this is only an issue when using Sequelize with SQLite. I had no problems after switching to Postgres. This question still stands though.
In Sequelize, I have Server and Seller models with a many-to-many relationship. The join model is IgnoredSellers.
const Server = sequelize.define('server', {
id: {
type: DataTypes.INTEGER,
primaryKey: true
}
}, { timestamps: false });
const Seller = sequelize.define('seller', {
id: {
type: DataTypes.STRING,
allowNull: false,
primaryKey: true
},
title: {
type: DataTypes.STRING,
allowNull: false
}
}, { timestamps: false });
const IgnoredSeller = sequelize.define('ignored_seller', {}, { timestamps: false });
Server.belongsToMany(Seller, { through: IgnoredSeller });
Seller.belongsToMany(Server, { through: IgnoredSeller });
Here's a sample row in the servers table:
id
84805370821310096
When I try Server.findByPk(84805370821310096), the returned Server instance has an id of 84805370821310100, which looks like an incremented version of the stored value.
const server = await Server.findByPk(serverId); // 84805370821310096 is passed in
// Executing (default): SELECT `id` FROM `servers` AS `server` WHERE `server`.`id` = '84805370821310096';
console.log('SERVER:', server.id); // 84805370821310100 is returned
So when I try server.addSeller(seller), I get a foreign key constraint error because the Server instance ID 84805370821310100 doesn't match any ID in the server table.
// Continued from above code
const seller = await Seller.findOne({ where: { title: sellerTitle }});
const ignoredSeller = await server.addSeller(seller);
// Executing (default): INSERT INTO `ignored_sellers` (`serverId`,`sellerId`) VALUES (84805370821310100,'amp');
// Failed to insert ignored seller: ForeignKeyConstraintError [SequelizeForeignKeyConstraintError]: SQLITE_CONSTRAINT: FOREIGN KEY constraint failed
What's causing this to happen?
You have to define IgnoredSeller like this -
const IgnoredSeller = sequelize.define(
"ignored_seller",
{
sellerId: Sequelize.INTEGER,
serverId: Sequelize.INTEGER,
},
{
timestamps: false
}
)
My idea is to have the ability to add multiple strings at keyword, I've been told to use foreign keys and so am I. But I can't figure out why it's not working properly. Any ideas?
My code is as follows
user.js
var User = sequelize.define('user', {
username: Sequelize.STRING,
myhash: Sequelize.TEXT,
mysalt: Sequelize.STRING,
keyword: Sequelize.STRING
});
var keywordData = sequelize.define('keywordData', {
keywords: Sequelize.STRING
})
User.hasMany(keywordData)
keywordData.belongsTo(User)
User.js
router.post("/newkeyword", function(req, res) {
keywordData.update(
{keywordData: req.body.newkeyword},
{where: {id: req.user['id']}}
)
})
You forgot to indicate a foreignKey option in the second association definition as well as create an auto-increment id for keywordData model.
var keywordData = sequelize.define('keywordData', {
id: { type: Sequelize.INTEGER, autoIncrement: true, primaryKey: true, },
keywords: { Sequelize.STRING }
})
Hence, your association should be like this:
User.hasMany(keywordData)
keywordData.belongsTo(User, {foreignKey: 'keyword', targetKey: 'keywords' })
Also you an refer this document for more details.
I want to build a sequelize relationship that represents : An item is composed by a specific amount of others items.
Database tables
Item (itemId, name)
Ingredient (ingredientId, itemParentId, itemChildrenId, amount)
Sequelize models
// Item.js
class Item extends Sequelize.Model { }
Item.init({
itemId: {
type: Sequelize.INTEGER,
autoIncrement: true,
primaryKey: true
},
name: Sequelize.STRING,
}, {
sequelize: db,
})
// Ingredient.js
class Ingredient extends Sequelize.Model { }
Ingredient.init({
ingredientId: {
type: Sequelize.INTEGER,
autoIncrement: true,
primaryKey: true
},
amount: Sequelize.INTEGER,
}, {
sequelize: db,
})
And I am just trying to write the correct sequelize association to match my database logic, so I tried :
// Association.js
Item.belongsToMany(Item, { through: Ingredient, as: 'ingredients', foreignKey: 'itemParentId' })
But I'm having this error Unknown column 'ingredients->ingredient.ingredientItemId' in 'field list', which is true but I do not know how to specify the right keys/columns.
Any help, please!
I see few problems: First, you're performing Item.init within the Ingredient model. Probably a mistake on your part. Change it to Ingredient.init.(personally i never used this "init" api, i define models differently, so i'm not sure how it works)
Second, change the primary keys of both Ingredient and Item to be just "id", like:
id: {
type: Sequelize.INTEGER,
autoIncrement: true,
primaryKey: true
}
Also, your association isn't correct, it needs to be through a junction table:
Item.belongsToMany(Ingredient, { through: "ItemIngredient"})
Note that "through" referes here to a table name, that Sequelize will create automatically if you're using model.sync(), and if not- you will need to create it yourself(or with a migration, which i recommend), with columns: itemId, ingredientId.
You also need to add the "reverse" association, like that:
Ingredient.belongsToMany(Item, { through: "ItemIngredient"})
I have the following two tables in Sequelize
const Tokens = sequelize.define("Tokens", {
id: {
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4,
primaryKey: true
},
active: {
type: DataTypes.BOOLEAN
}
});
and
const User = sequelize.define("Users", {
id: {
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4,
primaryKey: true
},
first_name: {
type: DataTypes.STRING
}
});
User.associate = models => {
models["Users"].hasMany(models["Tokens"], {foreignKey: 'userID', as: 'tokens_userid'});
};
I'm trying to run the following query in Sequelize.
const token = await db.Tokens.findOne({
where: {
id,
active: true
},
include: ["tokens_userid"]
});
But I'm getting the following error.
Error: Association with alias "tokens_userid" does not exists
My main goal is to get the user based on a Token ID. Now I would just move that association to the User table, but the problem with that later on I will want to get all the tokens for a given User ID. So I will run into this problem either way.
I tried adding the following line, but it was complaining about circular relations or something like that.
models["Tokens"].hasOne(models["User"], {foreignKey: 'userID', as: 'tokens_userid'});
How can I query either the Users or Tokens table and have it populate correctly with the relation?
I was able to solve this by adding the following line to my table.
models["Tokens"].belongsTo(models["User"], {foreignKey: 'userID', as: 'tokens_userid_from_token'});
Basically what I tried before but changed hasOne to belongsTo.
Hopefully this helps someone else.
I have two models Brand and Campaign.
A Brand can have many Campaigns
export default(sequelize, DataTypes)=> {
const Brand = sequelize.define('Brand', {
id: {
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4,
primaryKey: true,
},
})
Brand.associate = models=> {
Brand.belongsToMany(models.Campaign, {
through: models.CampaignBrand,
foreignKey: 'brand',
})
}
return Brand
}
A Campaign can also have many Brand
export default(sequelize, DataTypes)=> {
const Campaign = sequelize.define('Campaign', {
id: {
type: DataTypes.UUID,
defaultValue: DataTypes.UUIDV4,
primaryKey: true,
},
})
Campaign.associate = models=> {
Campaign.belongsToMany(models.Brand, {
through: models.CampaignBrand,
foreignKey: 'campaign',
})
}
return Campaign
}
And here is through model:
export default(sequelize, DataTypes)=> {
const CampaignBrand = sequelize.define('CampaignBrand', {
// see enums
status: {
type: DataTypes.INTEGER,
allowNull: false,
},
roleText: {
type: DataTypes.STRING,
},
})
CampaignBrand.associate = models=> {
CampaignBrand.belongsTo(models.Campaign, {
foreignKey: 'campaign',
targetKey: 'id',
onDelete: 'CASCADE',
})
}
return CampaignBrand
}
In case I want to get Campaigns by brand. What should I do?
I have tried query likes document mentioned but it does not work for me
With Belongs-To-Many you can query based on through relation and select specific attributes. For example using findAll with through
User.findAll({
include: [{
model: Project,
through: {
attributes: ['createdAt', 'startedAt', 'finishedAt'],
where: {completed: true}
}
}]
});
I have found some ways to work around, but it is not what I am looking for:
SOLUTION 1:
Update belongsToMany Brand to hasMany CampaignBrand and the query by CampaignBrand.brand
SOLUTION 2:
Get Campaign by querying Brand
Any other advices?
Dialect: postgres
Database version: 9.4
Sequelize version: 4.2.1
I think you don't need this association in the the through model:
CampaignBrand.associate = models=> {
CampaignBrand.belongsTo(models.Campaign, {
foreignKey: 'campaign',
targetKey: 'id',
onDelete: 'CASCADE',
})
}
You already have the belongsToMany association in the definitions of Brand and Campaign, so I think you just need to create the CampaignBrand model with your status and roleText attributes.
As I understand it, then you can query brands through campaigns and it should return each brand element and its associated campaigns,
Brand.findAll({
include: [{
model: Campaign
}]
});
This answer is kinda old, but with belongstomany associations, you can use mixins.
https://sequelize.org/api/v6/class/src/associations/belongs-to-many.js~belongstomany
const campaigns = await CampaignModel.findAll();
const campaignsBrandsModels = await campaigns.getBrandsModels({
limit:1,
through: {where:{pivot_field:'pivot_value'} } // << You want this, i think!
});
Now, remember that, the mixins (get, set, count...) set their name with inflection library, so, a way to set the names without error (or without spending a lot of time searching the name in in the console) is setting an 'as' alias in the Association
CampaignBrand.belongsToMany(models.Campaign, {
through: models.CampaignBrand,
foreignKey: 'brand',
as: 'BrandsModels' //<<<< This is Super important! at least for easy usage
})
You can achieve this with an include in the findAll method too, BUT!
the 'limit: #' part will not work! (Will give you the error of "This only works with hasMany because separate: true")
I really hope this can help anyone, seya!