Frequently Asked Questions for MariaDB Xpand

What is Xpand?

Xpand is a distributed SQL database that maintains ACID properties while scaling transactions, writes, and reads, all while providing a simple, MariaDB-compatible SQL interface. Xpand was built from scratch from the ground up with a shared nothing architecture – there are no bottlenecks and no single points of failure. As your database grows, just add nodes, and Xpand will automatically rebalance data across the cluster.

When is Xpand a good choice?

Xpand is a good choice for applications rely on transactions, consistency, correctness, high availability, and low latency. Xpand can help scale seamlessly and is built for automatic fault tolerance and automatic database distribution. Xpand excels at OLTP scale and scales reads and writes while providing high availability and built-in fault tolerance. Xpand also offers high throughput parallel replication, support for columnar indexes, and allows you to scale up (and down) to handle seasonal workloads.

Is MariaDB Xpand open source?

No, Xpand is available as licensed, downloadable software.

On which platforms is Xpand supported?

Xpand is available anywhere that RHEL or CentOS 7.4 are available. You can also deploy using the Distributed Transactions service in MariaDB SkySQL.

How does Xpand scale transactions?

Xpand automatically distributed data across the cluster, ensuring multiple copies of all data. It uses Paxos to handle distributed transaction resolution, and writes are synchronously written to all replicas. Reads leverage multiple cores and nodes, and Xpand uses a distributed query optimizer to general optimal plans.

What steps are required to start an Xpand database?

Xpand is available in SkySQL as the Distributed Transactions service.

You can also launch Xpand anywhere CentOS 7 is available – see "Deploy Xpand Topology".

What steps are required to add more nodes to an existing Xpand database?

The short answer is: just add nodes. The new nodes are ready immediately to service queries, and in the background, Xpand will automatically rebalance data across the cluster to ensure even distribution across the cluster. For more details, see "Scale-Out with MariaDB Xpand".

What levels of redundancy are provided?

The desired level of redundancy (number of data replicas) can be configured via ALTER CLUSTER SET MAX_FAILURES.

Does the product support online backup operations?

Yes. For complete details, please see "Fast Backup and Restore with MariaDB Xpand". Xpand also supports MySQL operations such as mysqldump.