# Part 5: Blockchain state and transactions explained · Your first Rell app on Chromia · Learn Chromia

> This lesson covers how Chromia handles transactions and state. You'll follow a user-signed transaction through validation, see how it updates the dapp's…

Source: https://chromia.com/learn/book-review/blockchain-transactions/

Your first Rell app on ChromiaLesson 18 of 26

1. [01Your first Rell app on Chromia](https://chromia.com/learn/book-review/introduction/)
2. [02Set up your project](https://chromia.com/learn/book-review/setup/)
3. [03Rell project structure](https://chromia.com/learn/book-review/rell-structure/)

Part 1: Define your first entity

1. [04Overview](https://chromia.com/learn/book-review/book-entity/)
2. [05Create your first entity](https://chromia.com/learn/book-review/book-entity/tables/)
3. [06Add your first operation](https://chromia.com/learn/book-review/book-entity/basic-operations/)
4. [07Query every book](https://chromia.com/learn/book-review/book-entity/write-queries/)

Part 2: Add a related entity

1. [08Overview](https://chromia.com/learn/book-review/book-review-entity/)
2. [09Define the book review entity](https://chromia.com/learn/book-review/book-review-entity/tables/)
3. [10Add an operation for creating book reviews](https://chromia.com/learn/book-review/book-review-entity/basic-operations/)
4. [11Query all reviews for a book](https://chromia.com/learn/book-review/book-review-entity/write-queries/)

Part 3: Checking and validating inputs

1. [12Overview](https://chromia.com/learn/book-review/input-verification/)
2. [13Verify inputs](https://chromia.com/learn/book-review/input-verification/input-verification/)
3. [14Return structured results from queries](https://chromia.com/learn/book-review/input-verification/structure/)

Part 4: Signing transactions and filtering queries

1. [15Overview](https://chromia.com/learn/book-review/sign-transaction/)
2. [16Sign a transaction](https://chromia.com/learn/book-review/sign-transaction/sign-transaction/)
3. [17Filter and sort query results](https://chromia.com/learn/book-review/sign-transaction/structure/)

Part 5: Blockchain state and transactions explained

1. [18Overview](https://chromia.com/learn/book-review/blockchain-transactions/)
2. [19How blockchain state and transactions work](https://chromia.com/learn/book-review/blockchain-transactions/query-transaction/)
3. [20Walking through an example](https://chromia.com/learn/book-review/blockchain-transactions/example/)

Part 6: Create the client

1. [21Overview](https://chromia.com/learn/book-review/build-client/)
2. [22Prerequisites](https://chromia.com/learn/book-review/build-client/prerequisites/)
3. [23Establishing a connection to Chromia](https://chromia.com/learn/book-review/build-client/sign-transaction/)
4. [24Query the blockchain using postchain-client](https://chromia.com/learn/book-review/build-client/query-blockchain/)
5. [25Complete the example](https://chromia.com/learn/book-review/build-client/complete-example/)

1. [26What’s next?](https://chromia.com/learn/book-review/what-next/)

[Learn](https://chromia.com/learn/)[Your first Rell app on Chromia](https://chromia.com/learn/book-review/)

18 / 26Part 5: Blockchain state and transactions explainedBeginner

# Part 5: Blockchain state and transactions explained

This lesson covers how Chromia handles transactions and state. You'll follow a user-signed transaction through validation, see how it updates the dapp's table state, and learn how it gets committed to the blockchain.

You'll also query your dapp's current state and fetch every transaction stored on the blockchain, which shows you how blockchain transactions relate to the table state.

To finish, you'll walk through an example that changes a book's title and observe the effect on both the blockchain and the state.

## In this lesson

1. [How blockchain state and transactions work](https://chromia.com/learn/book-review/blockchain-transactions/query-transaction/)
2. [Walking through an example](https://chromia.com/learn/book-review/blockchain-transactions/example/)

[Begin lesson →](https://chromia.com/learn/book-review/blockchain-transactions/query-transaction/)

Written for this site from Chromia’s public course. Code samples are the course’s own.

[← Previous**Filter and sort query results**](https://chromia.com/learn/book-review/sign-transaction/structure/)[Next →**How blockchain state and transactions work**](https://chromia.com/learn/book-review/blockchain-transactions/query-transaction/)