Shopify primarily uses MySQL, unless something major has changed recently. They've done a number of conference talks and engineering blog posts about their usag

Shopify primarily uses MySQL, unless something major has changed recently. They've done a number of conference talks and engineering blog posts about their usage of MySQL, see e.g. https://www.google.com/search?q=mysql+site%3Ashopify.engineering https://www.google.com/search?q=mysql+site%3Ashopify.enginee...