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Table of contents
Purpose & History of QLDB
Challenges in Traditional Approach
Characteristics of QLDB
Amazon QLDB Benefits/Features
(1) Immutable and Transparent
(2) Easy Access
 (3) Cryptographically Verifiable
(4) Easy to Scale
(5) Easy to Set Up
(6) PartiQL Support
(7) Semantics and Transactional Consistency
Amazon QLDB Use-Cases
Retail & Supply Chain
Frequently Asked Questions
What is Amazon Quantum Ledger Database?
What are the advantages of QLDB? 
What are the alternatives of QLDB?
Last Updated: Mar 27, 2024

Amazon Quantum Ledger Database(QLDB)

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We already have various types of databases in AWS, like Amazon Neptune ( A Graphical database) and Amazon Timestream (A time series serverless Database). Along with these databases, Amazon introduced a new database designed to help with problems of precision and correctness. QLDB is a new class of ledger database services designed to keep a complete and verifiable history of all changes to your application data.

Today, we will learn about another unique database Amazon Quantum Ledger Database (QLDB).

                                                                                                                                                                        Source: fibonalabs


Amazon Quantum Ledger Database (QLDB) is a Database used to check the correctness of any operation or transaction. QLDB makes it simple to explore your data history or lineage and see how your application has evolved. This, in turn, makes it clear to build a system of record type application or application where having that complete history that is verifiable is critical.

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Purpose & History of QLDB

Amazon build QLDB to deal with the problems of building a system of record application, and these are problems that amazon has seen several of its customers face, and indeed we have met them ourselves. But it turns out that we are not the first people to deal with these problems. 


                                                           Source: Osano

For nearly the past fifty-five hundred years, when you look at civilization worldwide, people have been dealing with the challenge of keeping accurate records and verifiable history for a very long time.

Ancient people record the data, like information on the distribution of grain or barley from a large temple to the people surrounding it.

As the writing form evolved over the years, it became more and more used broadly in conducting business, recording business agreements and legal proceedings, etc. Mesopotamians realized that they needed to establish the authenticity of the documents they were writing. So they invented the first form of signing called the cylinder seal. 

Again moving forward to thousands of years, we get to one of the most pivotal moments in record-keeping: the advent of formalization of double-entry accounting or double-entry bookkeeping. Indeed, this is where the concept of the ledger as we know it today, and as we discussed it in the context of our product and many blockchains or ledger product, comes from before the double-entry accounting approach was invented and became used in business.


And now today, this brings us to record-keeping. A lot has changed through the past thousand years. However, record-keeping and maintaining a history of business details, transactions, and things that have happened is still really fundamental to everything we do. In many cases, it is far more pervasive.

And a lot more critical than it has ever been. 


There are several examples across the industries where it is clear that maintaining accurate and complete historical records is vital, for instance, in banking and finance.

Challenges in Traditional Approach

During the traditional process, customer faces various types of challenges. They are :

  1. Resource Intensive
  2. Difficult to manage and scale.
  3. Error-prone and incomplete 
  4. Impossible to verify.

So we started using blockchain technology and distributed ledgers, but we also faced some challenges like:

  1. They are designed for a very unique and different purpose.
  2. They add unnecessary complexity.
  3. They are challenging to maintain.
  4. Hard to scale.

Characteristics of QLDB

We will see some of the Characteristics  of the Amazon Quantum Ledger Database:

  1. Immutable: Maintain a sequenced record of all changes to your data, which cannot be deleted or modified. You can query and analyze the entire history.
  2. Cryptographically: use cryptography to generate a secure output of your data history.
  3. Highly Scalable: Executes 2-tier as many transaction ledgers in a common blockchain Framework. 
  4. Easy to use: easy to use, using familiar database capabilities like SQL and APIs for querying the data.

Amazon QLDB Benefits/Features

Amazon QLDB comes with several features and benefits. Let’s discuss them.

(1) Immutable and Transparent

The first and foremost feature of QLDB is immutability. It is possible only because of the use of the append-only Journal. The journal stores a sequenced and correct entry of every data change within the system.

The Journal is append-only and can store the history of any transaction or data change. This also means that any stored data cannot be modified or changed.

If there is a need to remove data from a database, the ledger will keep the knowledge of the deletion with its previous states and values.

(2) Easy Access

Amazon QLDB knows that it is essential for the data to be accessed easily by the user. That is why the application lets you check the entire history with ease. To review, the user requires to use the querying language. They can check both the transaction history and the historical changes.

 (3) Cryptographically Verifiable

Each of the switches is verifiable through cryptographic hashes connected to each switch of data. It creates a precise and concise summary of all the changes one made to the data. It is known as a secure summary or digest. 

Taking some information and making changes will create a secure summary to prove the change. It is used to check the verifiability and integrity of the data. Using QLDB’s API, we can digest the data.

You can use the QLDB to know the data’s history and make the most out of its querying interface.

(4) Easy to Scale

Amazon QLDB is scalable. It offers the choice of automatic scaling, which is seamless. There is no need to do manual hard work to scale your application. Moreover, if you use an enterprise blockchain framework, QLDB will also work with it to improve its performance.

QLDB is way faster than traditional blockchain framework data transfers because these transactions are 2-3 times faster.

(5) Easy to Set Up

Amazon QLDB is easy to set up as it doesn’t need servers for provision capacity and management. You can create a new ledger present in the AWS Command Line Interface, AWS Management Console, or other methods within a few minutes.

(6) PartiQL Support

QLDB support PartiQL. It is a query language with the help of SQL-compatible access to the QLDB. The user can relate to the document-oriented data model. 

The Amazon QLDB supports the Document-oriented Data Model. It offers a well-structured data model and enables users to use flexible data storage.

(7) Semantics and Transactional Consistency

QLDB supports the ACID property

The ACID stands for atomicity, consistency, isolation, and durability. Other key database features include complete serialisation.

Also see, Amazon Hirepro

Amazon QLDB Use-Cases

Now, we will look at the Amazon QLDB use cases. The Amazon QLDB use-cases are essential to glance at what QLDB offers.


As we already see, blockchain in manufacturing QLDB will only make things more efficient to use.

This means it will appropriately document each of its batches. In the end, they equip with the knowledge of discovering the parts if something goes wrong during the distribution life cycle of an item.


The blockchain in the trade finance sector can benefit immensely using a Journal-first approach. Using a solution that QLDB powers can track critical data, including bank account loans, transactions, etc.

These organizations also do not need to create a custom-based solution.


The blockchain for the insurance sector can work efficiently and effectively with the Amazon QLDB. They can have a good history of the transactions and result in better claims. As of now, Insurance companies use complex auditing solutions that use old technologies such as relational databases.

Using the QLDB, they can keep the actual historical data about transactions and resolve any potential conflict in the insurance sector. The cryptographically secure ledger also ensures that no data is compromised or manipulated.

Retail & Supply Chain

With QLDB, retailers can take proper care of their supply chain and access information about a product in their supply chain and retail outlets.

QLDB can help in two sections —

  • Blockchain in retail
  • Blockchain for supply chain

For example, they can know when the items are shipped, when they will reach the retail, and who is handling the shipment. These details are crucial and help retail keep stock modernized and ready to dispatch. Their logistics are also enhanced with better transactional and historical data.

Frequently Asked Questions

What is Amazon Quantum Ledger Database?

The Amazon Quantum Ledger Database (Amazon QLDB) is a fully managed ledger database that offers a centrally trusted authority with a visible, immutable, and cryptographically verifiable transaction record.

What are the advantages of QLDB? 

  • Highly secure  
  • High speed  
  • Immutable 
  • Serverless

What are the alternatives of QLDB?

QLDB has many alternatives like MySQL and PostgreSQL, so people prefer these over QLDB.


This article extensively discusses Amazon Quantum Ledger Database (QLDB) and its features. We have also discussed the purpose, characteristics, advantages, and disadvantages of QLDB.

We hope that this blog has helped you enhance your knowledge regarding Amazon Quantum Ledger Database and if you would like to grasp more, check out our articles on Coding Ninjas. If you liked this article, we recommend you to check out these fantastic articles on SQL problemsBlockchainAmazon AWS, and many more.

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