SQLite with expo-sqlite in React Native - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is expo-sqlite used for in React Native?

It is a library that allows you to use a lightweight SQL database (SQLite) inside your React Native app to store and manage data locally on the device.

beginner

How do you open or create a database using expo-sqlite?

You use SQLite.openDatabase('name.db') which opens the database if it exists or creates it if it doesn't.

intermediate

What method is used to run SQL commands like creating tables or inserting data?

You use db.transaction(tx => { tx.executeSql(sql, params, success, error) }) to run SQL commands inside a transaction.

intermediate

Why do we use transactions when working with expo-sqlite?

Transactions ensure that a group of SQL commands run safely together. If one command fails, the whole transaction can be rolled back to keep data consistent.

intermediate

How can you retrieve data from the database using expo-sqlite?

Inside a transaction, use executeSql with a SELECT query. The results are in the resultSet.rows._array property inside the success callback.

Which function opens or creates a SQLite database in expo-sqlite?

A SQLite.openDatabase('mydb.db')

B SQLite.createDatabase('mydb.db')

C SQLite.connect('mydb.db')

D SQLite.initDatabase('mydb.db')

The correct method to open or create a database is SQLite.openDatabase('mydb.db').

What is the purpose of the transaction method in expo-sqlite?

A To open the database connection

B To backup the database

C To close the database

D To run multiple SQL commands safely as a group

Transactions group SQL commands so they run safely together, ensuring data integrity.

Where do you find the rows returned by a SELECT query in expo-sqlite?

A resultSet.records

B resultSet.rows._array

C resultSet.rowsArray

D resultSet.data

The rows returned are inside resultSet.rows._array in the success callback.

Which SQL command creates a new table in expo-sqlite?

A CREATE TABLE IF NOT EXISTS tablename (...)

B NEW TABLE tablename (...)

C MAKE TABLE tablename (...)

D ADD TABLE tablename (...)

The correct SQL syntax to create a table if it doesn't exist is CREATE TABLE IF NOT EXISTS.

What happens if one SQL command fails inside a transaction?

A The database closes automatically

B Only the failed command is ignored, others continue

C The whole transaction rolls back and no changes are saved

D The app crashes

Transactions ensure all commands succeed or none do, so failure rolls back all changes.

Explain how to create a simple table and insert data using expo-sqlite in React Native.

Think about opening the database, then running SQL commands inside a transaction.

Describe how to retrieve and display data from a SQLite database using expo-sqlite.

Focus on running a SELECT query and accessing the results in the callback.