보관 패턴

db.sales.insertMany( [
   {
      customer_name: "Hiroshi Tanaka",
      products: [
         {
            product_id: "P1001",
            name: "Wireless Headphones",
            quantity: 1,
            price: 59.99
         },
         {
            product_id: "P1002",
            name: "Phone Charger",
            quantity: 2,
            price: 14.99
         }
      ],
      total_amount: 89.97,
      date: ISODate("2025-01-30T10:15:00Z")
   },
   {
      customer_name: "Aisha Khan",
      products: [
         {
            product_id: "P1003",
            name: "Laptop",
            quantity: 1,
            price: 899.99
         }
      ],
      total_amount: 899.99,
      date: ISODate("2018-11-20T15:45:00Z")  // Over 5 years ago
   },
   {
      customer_name: "Fatima Al-Farsi",
      products: [
         {
            product_id: "P1006",
            name: "Gaming Mouse",
            quantity: 1,
            price: 49.99
         },
         {
            product_id: "P1007",
            name: "Mechanical Keyboard",
            quantity: 1,
            price: 129.99
         }
      ],
      total_amount: 179.98,
      date: ISODate("2017-06-15T12:00:00Z")  // Over 5 years ago
   },
   {
      customer_name: "Nguyen Minh",
      products: [
         {
            product_id: "P1008",
            name: "Bluetooth Speaker",
            quantity: 2,
            price: 39.99
         }
      ],
      total_amount: 79.98,
      date: ISODate("2025-01-26T09:20:00Z")
   }
] )

// Set a variable to five years before the time that the script runs
const fiveYearsAgo = new Date();
fiveYearsAgo.setFullYear(fiveYearsAgo.getFullYear() - 5);
// Write old sales to the 'archived_sales' collection
const writeOldSalesPipeline = [
   {
      $match: {
         date: { $lt: fiveYearsAgo }
      }
   },
   {
      $merge: {
         into: {
            db: "test",
            coll: "archived_sales",
         },
         on: "_id"
      }
   }
]
db.sales.aggregate(writeOldSalesPipeline)
// Delete old sales from the active 'sales' collection
try {
   db.sales.deleteMany(
      { date : { $lt: fiveYearsAgo } }
   );
} catch (e) {
   print (e);
}