Tag: Sequelize

Sequelize can add a foreign key constraint to the desired SQL table by using one of the following association methods: hasOne() belongsTo() Both hasOne and belongsTo() are Sequelize association methods that enable you to create a relation between two Sequelize models. The model from which you call the method is also known as the source… Continue reading Adding foreign key to a table using Sequelize

Sequelize provides a validate option that you can use to validate the attribute values passed into your models. Suppose you have a Users table with two columns: firstName and email. When defining the model for the table, you can pass the validate option to any of your attributes that requires validation. To validate the email… Continue reading How to validate values passed into Sequelize models

Sequelize where option accepts an object describing the WHERE clause to add to your generated SQL query. For example, suppose you have a table named Users with the following details: id  firstName   1  John await User.findAll({  where: { firstName: “John” }, }); We can also create more complex conditions by adding operators from Sequelize Op… Continue reading Using the where option in Sequelize methods

Sequelize has two data types that you can use to put date-related values: The DATEONLY type that converts to the SQL DATE format The DATE type that converts to the SQL DATETIME format const Invoice = sequelize.define(“Invoice”, {  invoiceDate: {   type: Sequelize.DATEONLY,  },  paymentDate: {   type: Sequelize.DATE,  },  amount: {   type: Sequelize.INTEGER,  }, }, {… Continue reading How to format the date for date types values in Sequelize

The Sequelize model you create using the sequelize.define() method comes with a sync() method that you can use to create a table.The table created using the sync() method will follow the model definition for its column(s).For example, suppose you have the following User model defined in your code: The call to User.sync() above will cause… Continue reading How to create a database table using Sequelize code

Sequelize supports running SQL statements under a transaction by using the Transaction object. To start a transaction using Sequelize, you need to create a Transaction object by calling sequelize.transaction() as shown belowconst trx = await sequelize.transaction(); The code above creates a Transaction instance named trx.When we run query methods from model, we need to pass the  object as the transaction option. const trx =… Continue reading Creating a transaction sequence using Sequelize