Hi @loujiang ,
Databricks Runtime is not a vanilla Apache Spark distribution. DBR is built on top of a highly optimized version of Apache Spark, but also adds enhancements and additional components that substantially improve usability, performance, and security beyond what's in the open-source release. This means Databricks can - and regularly does - ship Spark features ahead of their upstream release.
Looking directly at the DBR 14.1 release notes, the Spark changelog section lists: Databricks Runtime 14.1 (EoS) | Databricks on Google Cloud
[SPARK-44788] [SC-142980][CONNECT][PYTHON][SQL] Add from_xml and schema_of_xml to pyspark, spark connect and sql function
This JIRA ticket was cherry-picked into DBR 14.1, even though DBR 14.1 runs on Spark 3.5.0. Databricks applied this patch internally before it landed in an official Apache Spark release.
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