# Part 4: Signing transactions and filtering queries · Your first Rell app on Chromia · Learn Chromia

> This lesson shows you how to sign transactions so the network can verify who sent them. You will also build an admin function, book_keeper, that adds and…

Source: https://chromia.com/learn/book-review/sign-transaction/

Your first Rell app on ChromiaLesson 15 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/)

15 / 26Part 4: Signing transactions and filtering queriesBeginner

# Part 4: Signing transactions and filtering queries

This lesson shows you how to sign transactions so the network can verify who sent them. You will also build an admin function, `book_keeper`, that adds and manages the books users can review.

After that, you will write Rell queries that filter and sort data, starting with queries that return reviews filtered and ordered by rating.

## In this lesson

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

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

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

[← Previous**Return structured results from queries**](https://chromia.com/learn/book-review/input-verification/structure/)[Next →**Sign a transaction**](https://chromia.com/learn/book-review/sign-transaction/sign-transaction/)