config.jsto use a new DB name,
validations_developmentto distinguish the DB from other modules. Stop after creating the DB and follow the steps below to create a one-to-many SQL relationship with through table attributes with Sequelize.
itemstables in our DB by running migrations.
sequelize-clito generate a seed data migration file.
namecolumn of the
itemstable. Let's try to violate this constraint.
violateDbConstraint.mjsscript to try to violate our DB constraint.
process.argvwill be undefined.
DatabaseErrorclass from Sequelize. Update
violateDbConstraint.mjsto perform different logic for database errors.
item.mjsmodel to add an
allowNullvalidation for the
nameattribute. Let's create a
violateModelValidation.mjsscript that performs special logic for validation errors by importing the
ValidationErrorclass from Sequelize.
ValidationErrorItemobject and sending an error message to the client via a response. This message could be displayed in the form with invalid input client-side.
violateModelValidation.mjsto include the following error-handling logic.