[GitHub] [beam] anantdamle commented on a change in pull request #13554: [BEAM-11460] Support reading Parquet files with unknown schema

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anantdamle commented on a change in pull request #13554:
URL: https://github.com/apache/beam/pull/13554#discussion_r548551154



##########
File path: sdks/java/io/parquet/src/main/java/org/apache/beam/sdk/io/parquet/ParquetIO.java
##########
@@ -152,6 +162,38 @@
  * *
  * }</pre>
  *
+ * <h3>Reading records of an unknown schema</h3>
+ *
+ * <p>To read records from files whose schema is unknown at pipeline construction time or differs
+ * between files, use {@link #parseGenericRecords(SerializableFunction)} - in this case, you will
+ * need to specify a parsing function for converting each {@link GenericRecord} into a value of your
+ * custom type.
+ *
+ * <p>For example:
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<Foo> records =
+ *     p.apply(ParquetIO.parseGenericRecords(new SerializableFunction<GenericRecord, Foo>() {
+ *       public Foo apply(GenericRecord record) {
+ *         // If needed, access the schema of the record using record.getSchema()
+ *         return ...;
+ *       }}));
+ *
+ * // For reading from filepatterns
+ *  PCollection<String> filepatterns = p.apply(...);

Review comment:
       Done, also added some indentation




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