Gatsby is a popular framework for building statically rendered React sites. However, in some cases, data needed for these sites may come from databases like Postgres. To address this issue, the gatsby-source-graphql plugin can be used to set any GraphQL API as a Gatsby data source. Additionally, Hasura can expose an existing Postgres database over GraphQL instantly. A boilerplate and tutorial by Karthik Venkateswaran are available for quick setup and integration of large datasets from Postgres into Gatsby sites using GraphQL.