Managing concurrent access to a resource, be it a row, a table, or a single value, is easy if no one is trying to modify the underlying data. But what happens if someone changes data while someone else is reading it? Even better, what could happen if two or more users try to change the same data at the same time? Well, there are a couple of options. The easiest is to just ask everyone to queue up, the other is to have multiple versions of the data available over time so that no one must wait for the changes to be finished. Let's explore both the options with Lara Rubbelke and Davide Mauri on Azure Friday. Chapters 00:00 – Introduction 01:50 – DEMO: Locking behavior 03:20 – DEMO: Default "read committed snapshot" behavior 05:20 – Migrating from SQL Server to Azure SQL DB 06:42 – DEMO: snapshot isolation level 12:12 – Wrap-up Recommended resources ■ Transaction locking and row versioning guide – https://aka.ms/azfr/726/01 ■ SET TRANSACTION ISOLATION LEVEL (Transact-SQL) – https://aka.ms/azfr/726/02 ■ Azure SQL Database – https://aka.ms/azfr/726/03 ■ Create a Pay-as-You-Go account (Azure) – https://aka.ms/azfr/726/payg ■ Create a free account (Azure) – https://aka.ms/azfr/726/free Connect with us ■ Lara Rubbelke | @SQLGal – https://twitter.com/SQLGal ■ Davide Mauri | @MauriDB – https://twitter.com/MauriDB ■ Azure Friday | @AzureFriday – https://twitter.com/AzureFriday #MicrosoftAzure #AzureFriday #AzureSQL