I knew Brent and Erik wouldn't touch replication, so I figured I'd give it a whirl.
My good, old friend replication
I have a love-hate relationship with replication. Mostly hate due to latency and errors, but it does serve its purpose. Before Availability Groups came out, I used Transactional Replication to copy data from the production OLTP database to another server so that we could offload reports.
At first glance, SQL Server's transactional replication seems like it's useful for moving data around in all sorts of situations: it works in Standard Edition, it's not synchronous, and you can have multiple subscribers.
Why People Want Replication to Test and Pre-Production Environments
The best part about transactional replication is that it's flexible. And the worst thing about transactional replication is that it's flexible. A poor replication configuration will cause you performance pains and increase your risks of development and administrative errors. Here's one important design principle: isolate your replication subscriber tables from one another, and from non-subscriber tables.…
SQL Server transactional replication is a blessing and a curse. It's a great developer tool that lets you scale out data to multiple servers, even using Standard Edition. But as your business picks up, your datasets get larger, and your customers grow more demanding, replication can start to fall behind. You need to learn how…
It was the best of times, it was the worst of times. I was a SQL Server DBA, and if something went wrong in Transactional Replication I needed to find out about it right away and help keep things healthy, day or night. Here's what I learned from that experience about monitoring replication.
If you're just getting started and need an introduction to transactional replication, head over here.
If SQL Server's Transactional Replication was an animal, it would be a cockroach. It's not pretty, but it's resourceful and strong. Once you get even a small amount of replication in your environment it starts spreading everywhere. And if it gets out of control-- well, in that case you've got no choice but to pretty…
As businesses grow, many teams start considering scale out database solutions but they're cautious - they want to know how to keep data up to date in multiple places. In theory, you can use log shipping, mirroring, or AlwaysOn Availability groups. While this answers the literal question, what people really mean is usually very different.…
The more SQL Servers I see, the more scared I get. There are a staggering number of ways that your server can sneak around behind you and ... well, let's just say you shouldn't drop the soap in the datacenter.
As part of my health checks, I'm used to verifying that full backups are done regularly, but that's not enough.
I want to make something clear: high availability is not load balancing. The two options don't have to be mutually exclusive, but they aren't the same thing. Several months ago, I wrote about resolving write conflicts. Some of the approaches I mentioned for resolving write conflicts (such as taking a "last write wins" approach) involved…
Anyone who has worked with replication has run into problems caused by conflicting data. I've lost enough sleep over replication to know that having an effective plan for conflict resolution is important to keeping replication running and healthy.
What Causes Conflicts?
