트랜잭션으로 데이터 일관성 강화

use test
db.products.insertMany(   [      {         sellerId: 456,         name: "sweater",         price: 30,         rating: 4.9      },      {         sellerId: 456,         name: "t-shirt",         price: 10,         rating: 4.2      },      {         sellerId: 456,         name: "vest",         price: 20,         rating: 4.7      }   ])

use test
db.sellers.insertOne(   {      id: 456,      name: "Cool Clothes Co",      location: {         address: "21643 Andreane Shores",         state: "Ohio",         country: "United States"      },      phone: "567-555-0105",      products: [         {            name: "sweater",            price: 30         },         {            name: "t-shirt",            price: 10         },         {            name: "vest",            price: 20         }      ]   })

// Start a sessionsession = db.getMongo().startSession( { readPreference: { mode: "primary" } } );productsCollection = session.getDatabase("test").products;sellersCollection = session.getDatabase("test").sellers;
// Start a transactionsession.startTransaction( { readConcern: { level: "local" }, writeConcern: { w: "majority" } } );
// Operations inside the transactiontry {   productsCollection.updateOne(      { sellerId: 456, name: "vest" },      { $set: { price: 25 } }   );   sellersCollection.updateOne(      { },      { $set: { "products.$[element].price": 25 } },      { arrayFilters: [ { "element.name": "vest" } ] }   );} catch (error) {   // Cancel transaction on error   session.abortTransaction();   throw error;}// Commit the transaction using write concern set at transaction startsession.commitTransaction();session.endSession();