Transactions

Tigris provides global, ACID transactions with strict serializability using optimistic concurrency control. The transactions allow multiple clients to concurrently read and write data in the database with strong consistency guarantees.

Transactions in Tigris work across collections and documents without any restrictions. Unlike some other document databases, there are no confusing read or write concerns to configure, and no cross-shard caveats.

Sync
Async

TigrisDatabase db = client.getDatabase();
db.transact(
    tx -> {
        try {
            // retrieve transaction aware collection
            TigrisCollection<User> userCollection = db.getCollection(User.class);
            User emma = userCollection.readOne(Filters.eq("id", emma.getId()));
            User lucy = userCollection.readOne(Filters.eq("id", lucy.getId()));

            // reduce emma's balance by 10
            userCollection.update(
            Filters.eq("id", emma.getId()),
            UpdateFields.newBuilder().set("balance", emma.getBalance() - 10).build());

            // increment lucy's balance by 10
            userCollection.update(
            Filters.eq("id", lucy.getId()),
            UpdateFields.newBuilder().set("balance", lucy.getBalance() + 10).build());
        } catch (Exception ex) {
            // throw it to rollback ongoing transaction
            throw new IllegalStateException(ex);
        }
    }
);

TigrisAsyncDatabase db = asyncClient.getDatabase();
db.beginTransaction(new TransactionOptions())
  .whenComplete((session, throwable) -> {
      if (throwable != null) {
          // handle exception
      }
      try{
          // retrieve transaction aware collection
          TransactionTigrisCollection<User> userCollection = session.getCollection(User.class);
          User emma = userCollection.readOne(Filters.eq("id", emma.getId()));
          User lucy = userCollection.readOne(Filters.eq("id", lucy.getId()));

          // reduce emma's balance by 10
          userCollection.update(
              Filters.eq("id", emma.getId()),
              UpdateFields.newBuilder().set(
                  "balance",
                  emma.getBalance() - 10
              ).build()
          );

          // increment lucy's balance by 10
          userCollection.update(
              Filters.eq("id", lucy.getId()),
              UpdateFields.newBuilder().set(
                  "balance",
                  lucy.getBalance() + 10
              ).build()
          );

          // commit transaction
          session.commit();
      } catch(Exception ex) {
          // handle ex
          // in case of an error, rollback
          session.rollback();
      }
  }
);