10_transactions_and_concurrency

SQL Transaction Management

Overview

This repository provides a guide on how to manage transactions in SQL databases. Transactions are essential for ensuring data integrity and consistency when executing multiple SQL statements that depend on each other.

Contents

0. Introduction to Transactions
1. Creating a Transaction
2. Concurrency and Locking
3. Concurrency Problems
4. Transaction Isolation Levels
5. READ UNCOMMITTED Isolation Level
6. READ COMMITTED Isolation Level
7. REPEATABLE READ Isolation Level
8. SERIALIZABLE Isolation Level

Introduction to Transactions

A transaction is a sequence of one or more SQL operations that are treated as a single logical unit of work. Transactions ensure that either all operations within the unit succeed or none of them are applied to the database.

Starting a Transaction

To start a transaction, use the BEGIN TRANSACTION or START TRANSACTION statement, depending on your SQL dialect.

Example:

BEGIN TRANSACTION;

-- SQL statements

COMMIT;