anchor.diff:  
   This option allows you to convert a hierarchical document into a flat structure suitable for a table-like storage.
   
  +== Configuration options
  +[cols="35%a,10%a,55%a",width=100,options="header,footer",role="table table-bordered table-striped"]
  +|=======================
  +|Property
  +|Default
  +|Description
  +
  +|`drop.tombstones`
  +|`true`
  +|The SMT removes the tombstone generated by Debezium from the stream.
  +
  +|`delete.handling.mode`
  +|`drop`
  +|The SMT can `drop`, `rewrite` or pass delete records (`none`). The `rewrite` mode will add a `__deleted` field set to `true` or `false` depending on the represented operation.
  +|=======================
  +
  +
   == Known limitations
   
   * Feeding data changes from a schemaless store such as MongoDB to strictly schema-based datastores such as a relational database can by definition work within certain limits only.
   Specifically, all fields of documents within one collection with the same name must be of the same type. Otherwise, no consistent column definition can be derived in the target database.
   * Arrays will be restored in the emitted Kafka Connect record correctly, but they are not supported by sink connector just expecting a "flat" message structure.
  -* Currently it's not possible to drop deletes and tomb stone events. This requirement is tracked as https://issues.jboss.org/browse/DBZ-563[DBZ-563].
  
positive.code: This SMT is supported only for the MongoDB connector.
  ====
  
  The Debezium MongoDB connector generates the data in a form of a complex message structure.
  The message consists of two parts:
  
  * operation and metadata
  * for inserts, the row data after the insert has been executed; for updates a patch element describing the altered fields
  
  The `after` and `patch` elements are Strings containing JSON representations of the inserted/altered data.
  E.g. the general message structure for a insert event looks like this:
  
negative.code: ----
  transforms=unwrap,...
  transforms.unwrap.type=io.debezium.connector.mongodb.transforms.UnwrapFromMongoDbEnvelope
  transforms.unwrap.drop.tombstones=false
  transforms.unwrap.delete.handling.mode=drop
  ----
  
  === Array encoding
  