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Data BIts – Episode 3 – Ginger Grant

Trainer and Consultant extraordinaire Ginger Grant stops by to talk Machine Learning, Data Bricks, Certifications, Norwegian pastries and proper chocolate frosting Find Ginger at Desert Isle SQL or on Twitter
The post Data BIts...

2020-04-01 (first published: )

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Blog Post

SQL Server HADR overview

My Pluralsight course for new SQL Server DBAs Image credit to Jeff (t) Back in June of 2019, I published this YouTube video covering the highlights of the various...

2020-03-25

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Blog Post

SQL Server Identity Skipping

My Pluralsight course for new SQL Server DBAs SQL Server may skip 1000 numbers on an Identity column if the server crashes. Here’s why: Too long, didn’t watch version:...

2020-02-04

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Refactoring SQL Code

By Steve Jones - SSC Editor

Comments posted to this topic are about the item Refactoring SQL Code, which is...

The Read Committed Snapshot Isolation behaviour

By Alessandro Mortola

Comments posted to this topic are about the item The Read Committed Snapshot Isolation...

Working with JSON/JSONB Data in PostgreSQL using Python

By sabyda

Comments posted to this topic are about the item Working with JSON/JSONB Data in...

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Question of the Day

The Read Committed Snapshot Isolation behaviour

I am currently working with Sql Server 2022 and AdventureWorks database. First of all, let's set the "Read Committed Snapshot" to ON:

use master;
go

alter database AdventureWorks set read_committed_snapshot on with no_wait;
go
Then, from Session 1, I execute the following code:
--Session 1
use AdventureWorks;
go

create table ##t1 (id int, f1 varchar(10));
go

insert into ##t1 values (1, 'A');
From another session, called Session 2, I open a transaction and execute the following update:
--Session 2
use AdventureWorks;
go

begin tran;
update ##t1 
set f1 = 'B'
where id = 1;
Now, going back to Session 1, what happens if I execute this statement?
--Session 1
select f1
from ##t1
where id = 1;
 

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