@tomei/product/migrations/004-add-productgroupid-to-product-product-group.js

NestJS package for product module

'use strict';

module.exports = {
  async up(queryInterface) {
    // Because Previously we use Composite Primary Key (Code, ProductId), we need
    // to remove first the old composite primary key, and because the composite PK
    // we used is also a Foreign Key, we need to also drop the foreign key
    // this function will find all the fk then drop the constraint
    const refFK = await queryInterface.getForeignKeyReferencesForTable(
      'product_ProductGroup',
    );
    refFK.forEach(async (fk) => {
      await queryInterface.sequelize.query(
        `Alter table product_ProductGroup drop FOREIGN KEY ${fk.constraint_name}`,
      );
    });

    // after all the FK is drop then we can safely drop the PK
    await queryInterface.sequelize.query(
      'Alter table product_ProductGroup DROP PRIMARY KEY',
    );

    // Create ProductGroupId column without PK constraint first
    await queryInterface.sequelize.query(
      'ALTER TABLE product_ProductGroup ADD ProductGroupId VARCHAR(30)',
    );

    // We cannot add ProductGroupId PK constraint if previous data is null, so
    // we UPDATING  a combination of CODE + productId in previously empty ProductGroupId
    await queryInterface.sequelize.query(
      "UPDATE product_ProductGroup SET ProductGroupId = SUBSTRING(CONCAT(code, ProductId),1,30) WHERE ProductGroupId IS NULL OR ProductGroupId = ''",
    );

    // Check if new primary key is not null an unique
    await queryInterface.sequelize.query(
      'ALTER TABLE product_ProductGroup MODIFY COLUMN ProductGroupId VARCHAR(30) NOT NULL UNIQUE',
    );

    // Adding PK constraint to ProductGroupId
    await queryInterface.sequelize.query(
      'ALTER TABLE product_ProductGroup ADD PRIMARY KEY (ProductGroupId)',
    );

    // After the primary key column is created, we need to re-adding the previous dropped FK
    refFK.forEach(async (fk) => {
      await queryInterface.sequelize.query(
        `ALTER TABLE product_ProductGroup ADD CONSTRAINT ${fk.constraint_name} FOREIGN KEY (${fk.columnName}) REFERENCES ${fk.referencedTableName}(${fk.referencedColumnName})`,
      );
    });
  },

  async down(queryInterface) {
    // Remove Primary Key first from the table
    await queryInterface.sequelize.query(
      'Alter table product_ProductGroup DROP PRIMARY KEY',
    );

    // Remove ProductGroupId from the table
    await queryInterface.sequelize.query(
      'Alter table product_ProductGroup DROP COLUMN ProductGroupId',
    );

    // Create a new Composite PK from Code and ProductId
    await queryInterface.sequelize.query(
      'ALTER TABLE product_ProductGroup ADD PRIMARY KEY (Code, ProductId)',
    );
  },
};