Description

Multi-DB distributes WordPress Multisite tables across up to 4096 databases, horizontally scaling networks with thousands of subsites to avoid the bottleneck of a single overloaded MySQL instance. Recommended for those who manage large multisite networks (universities, agencies with hundreds of client sites, SaaS platforms running on WordPress) and need to maintain fast queries even with a massive volume of subsites running in parallel.

Key Features of Multi-DB

  • Sharding across up to 4096 databases
    Partitions subsite tables into multiple MySQL databases based on the blog ID.
  • Global table mapping
    Keeps global tables (users, network options) in a dedicated database, separate from the shards.
  • Drop-in db.php
    Replaces the WordPress database access layer by installing a drop-in in wp-content.
  • Read and write balancing
    Allows you to configure master and slave servers to distribute queries across replica nodes.
  • Assisted data migration
    Includes routines to move tables from existing subsites to the multi-database schema without data loss.

Benefits of Multi-DB

  • True horizontal scalability
    Grow the network without relying solely on vertical upgrades of the primary database server.
  • Reduced I/O contention
    Distributes load across databases, reducing locks and queues during peak network hours.
  • Stable performance in large networks
    Subsite queries remain agile even when the network grows from hundreds to thousands of sites.
  • Growth-ready infrastructure
    Reserves shard slots that absorb new subsites without needing to replan the architecture from scratch.

Who is Multi-DB for?

  • Operators of WordPress Multisite networks with hundreds or thousands of subsites who experience MySQL stalls during peak hours.
  • Universities, publishing networks, and public institutions that maintain one institutional site per department within the same multisite installation.
  • Agencies and SaaS platforms that sell WordPress subsites as a service and need to scale database infrastructure without rewriting the application.

How to download Multi-DB

Multi-DB is available for download here in the Ultrapack. After downloading the .zip file, install it via Plugins > Add New > Upload Plugin, select the package, and network activate it. The sharding configuration and the db.php drop-in are applied according to the plugin’s instructions, preparing the database layer to distribute the subsites.

Geared towards those who manage large-scale WordPress network infrastructure, Multi-DB addresses the most critical point of multisite at scale: the single database that centralizes thousands of tables. By distributing data across multiple MySQL shards, it frees up space for sustainable growth, paves the way for read replicas, and keeps subsite response times predictable even when the network reaches volumes that would normally require rewriting the entire stack.

Frequently asked questions

Is WPMUDEV Multi-DB GPL-licensed?

Yes. WPMUDEV Multi-DB is distributed under the GPL (GNU General Public License). You may legally use, modify and redistribute it on as many sites as you want.

Can I use WPMUDEV Multi-DB on multiple sites?

Yes. You can use WPMUDEV Multi-DB on multiple sites. The number of sites connected to Ultrapack Auto Updater is limited by your plan.

How much does WPMUDEV Multi-DB cost at Ultrapack?

WPMUDEV Multi-DB costs US$2.99 as a single purchase, and it is also included in the subscription plans starting at US$12/mo (VIP I).

Does WPMUDEV Multi-DB include updates?

Yes. The current version of WPMUDEV Multi-DB is 3.2.5, published at Ultrapack on Sep 27, 2016. Subscribers update straight from the WordPress dashboard with UAU (Ultrapack Auto Updater).

Is WPMUDEV Multi-DB scanned before publication?

Yes. Every version of WPMUDEV Multi-DB goes through a malware scan (ClamAV and YARA rules, at UltraHub) before it is published.