WeichenXu123 commented on a change in pull request #34021: URL: https://github.com/apache/spark/pull/34021#discussion_r710134006
########## File path: python/pyspark/sql/dataframe.py ########## @@ -2536,6 +2536,28 @@ def withColumnRenamed(self, existing, new): """ return DataFrame(self._jdf.withColumnRenamed(existing, new), self.sql_ctx) + def withMetadata(self, columnName, metadata): + """Returns a new :class:`DataFrame` by updating an existing column with metadata. + + .. versionadded:: 3.3.0 + + Parameters + ---------- + columnName : str + string, name of the existing column to update the metadata. + metadata : dict + dict, new metadata to be assigned to df.schema[columnName].metadata + + Examples + -------- + >>> df_meta = df.withMetadata('age', {'foo': 'bar'}) + >>> df_meta.schema['age'].metadata + {'foo': 'bar'} + """ + if not isinstance(metadata, dict): + raise TypeError("metadata should be a dict") + return DataFrame(self._jdf.withMetadata(columnName, metadata), self.sql_ctx) Review comment: The metadata argument type is a dict , how does it pass to the java method `def withMetadata(columnName: String, metadata: Metadata)` and the metadata become a `Metadata` class type ? -- 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: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org