geoffreyclaude opened a new pull request, #130: URL: https://github.com/apache/datafusion-site/pull/130
## Which issue does this PR close? Closes https://github.com/apache/datafusion/issues/16756 (part of https://github.com/apache/datafusion/issues/14836) ## Rationale for this change DataFusion's SQL extensibility APIs are powerful but not widely known outside the contributor community. The library user guide added in https://github.com/apache/datafusion/pull/19265 documents the interfaces, but there wasn't a narrative introduction showing when and why you'd use each one. This post walks through real scenarios and shows which extension point to reach for in each case. ## What changes are included in this PR? New blog post at `content/blog/2025-12-18-extending-sql.md`. The post uses `CREATE EXTERNAL CATALOG` as a running example to show how custom syntax flows through DataFusion's parse → plan → execute pipeline. It then covers each extension point: parser wrapping for custom DDL, `ExprPlanner` for operators like `->>`, `TypePlanner` for dialect-specific types, and `RelationPlanner` for FROM-clause constructs like `PIVOT` and `TABLESAMPLE`. All code snippets link to working examples in `datafusion-examples`. There's also an architecture diagram showing where each hook fits in the pipeline. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
