📅  最后修改于: 2022-03-11 14:48:21.749000             🧑  作者: Mango
const { Model, DataTypes, Deferrable } = require("sequelize");
class Foo extends Model {}
Foo.init({
// instantiating will automatically set the flag to true if not set
flag: { type: DataTypes.BOOLEAN, allowNull: false, defaultValue: true },
// default values for dates => current time
myDate: { type: DataTypes.DATE, defaultValue: DataTypes.NOW },
// setting allowNull to false will add NOT NULL to the column, which means an error will be
// thrown from the DB when the query is executed if the column is null. If you want to check that a value
// is not null before querying the DB, look at the validations section below.
title: { type: DataTypes.STRING, allowNull: false },
// Creating two objects with the same value will throw an error. The unique property can be either a
// boolean, or a string. If you provide the same string for multiple columns, they will form a
// composite unique key.
uniqueOne: { type: DataTypes.STRING, unique: 'compositeIndex' },
uniqueTwo: { type: DataTypes.INTEGER, unique: 'compositeIndex' },
// The unique property is simply a shorthand to create a unique constraint.
someUnique: { type: DataTypes.STRING, unique: true },
// Go on reading for further information about primary keys
identifier: { type: DataTypes.STRING, primaryKey: true },
// autoIncrement can be used to create auto_incrementing integer columns
incrementMe: { type: DataTypes.INTEGER, autoIncrement: true },
// You can specify a custom column name via the 'field' attribute:
fieldWithUnderscores: { type: DataTypes.STRING, field: 'field_with_underscores' },
// It is possible to create foreign keys:
bar_id: {
type: DataTypes.INTEGER,
references: {
// This is a reference to another model
model: Bar,
// This is the column name of the referenced model
key: 'id',
// With PostgreSQL, it is optionally possible to declare when to check the foreign key constraint, passing the Deferrable type.
deferrable: Deferrable.INITIALLY_IMMEDIATE
// Options:
// - `Deferrable.INITIALLY_IMMEDIATE` - Immediately check the foreign key constraints
// - `Deferrable.INITIALLY_DEFERRED` - Defer all foreign key constraint check to the end of a transaction
// - `Deferrable.NOT` - Don't defer the checks at all (default) - This won't allow you to dynamically change the rule in a transaction
}
},
// Comments can only be added to columns in MySQL, MariaDB, PostgreSQL and MSSQL
commentMe: {
type: DataTypes.INTEGER,
comment: 'This is a column name that has a comment'
}
}, {
sequelize,
modelName: 'foo',
// Using `unique: true` in an attribute above is exactly the same as creating the index in the model's options:
indexes: [{ unique: true, fields: ['someUnique'] }]
});