DataTypes in Sequelize ORM

• Sequelize supports a wide range of data types that correspond to the data types available in different SQL databases like PostgreSQL, MySQL, SQLite, and Microsoft SQL Server. When you define a model and its attributes in Sequelize, you specify the data type of each attribute to ensure the data is stored correctly in the database.

Here is a list of some common Sequelize data types:

String/Binary Types

• DataTypes.STRING: Variable length string. You can specify a length as an argument (e.g., STRING(255)).
• DataTypes.TEXT: A large text block.
• DataTypes.CHAR: Fixed-length string.
• DataTypes.BINARY: Binary data.
• DataTypes.BLOB: A large block of binary data.

Numeric Types

• DataTypes.INTEGER: Integer.
• DataTypes.BIGINT: Large integer.
• DataTypes.FLOAT: Floating point number. Can specify precision as an argument.
• DataTypes.REAL: Floating point number. Similar to `FLOAT` in some databases.
• DataTypes.DOUBLE: Double precision floating point number.
• DataTypes.DECIMAL: Decimal number. Can specify precision and scale as arguments.

Date/Time Types

• DataTypes.DATE: Date and time without timezone.
• DataTypes.DATEONLY: Date without time.
• DataTypes.TIME: Time without date.
• DataTypes.BOOLEAN: Boolean value.

Other Types

• DataTypes.ENUM: Enumerated list of values.
• DataTypes.ARRAY(DataType): Array of values of the specified data type. Supported by specific databases like PostgreSQL.
• DataTypes.JSON: JSON object. Automatically parsed by Sequelize.
• DataTypes.JSONB: Binary format JSON object. Supported by specific databases like PostgreSQL.
• DataTypes.UUID: Universally unique identifier.

Example of Model Definition with DataTypes

• Here's an example of how you might define a model with various data types:

    const { Sequelize, DataTypes } = require('sequelize');

    const sequelize = new Sequelize('sqlite::memory:'); // Example for SQLite

    const User = sequelize.define('User', {

        name: DataTypes.STRING,

        bio: DataTypes.TEXT,

        age: DataTypes.INTEGER,

        isAdmin: DataTypes.BOOLEAN,

        birthday: DataTypes.DATEONLY,

        appointment: DataTypes.DATE,

        email: {

            type: DataTypes.STRING,

            allowNull: false,

            unique: true

        },

        salary: DataTypes.FLOAT,

        uuid: DataTypes.UUID

    });

• In this model, various Sequelize data types are used to define the properties of a `User`. These types ensure that Sequelize interacts with the database in the correct format for each attribute.

• It's important to choose the appropriate data type for each model attribute to accurately reflect the data and ensure the integrity of your database. Sequelize's support for a wide range of SQL data types allows for precise data modeling and manipulation.