anchor.diff:  Should not be invoked more than once for the same field.
   <4> Registers the customized value and schema converter for use with a specific field.
   
  -.Custom converter methods
  -The `configure()` and `converterFor()` methods are mandatory for each {prodname} custom converter:
  +[id="debezium-custom-converter-methods"]
  +=== Custom converter methods
  +
  +Implementations of the `CustomConverter` interface must include the following methods:
   
   `configure()`::
   Passes the properties specified in the connector configuration to the converter instance.
  
positive.code: ** Identifies the target `STRING` schema based on the value that is specified for the `schema.name` property.
  ** Converts ISBN data in the source column to `String` values.
  
  === {prodname} custom converter example
  [id="example-debezium-simple-custom-converter"]
  .A simple custom converter
  ====
  
negative.code: endif::product[]
  
  Each field in a {prodname} change event record represents a field or column in the source table or data collection.
  When a connector emits a change event record to Kafka, it converts the data type of each field in the source to a Kafka Connect schema type.
  Column values are likewise converted to match the schema type of the destination field.
  For each connector, a default mapping specifies how the connector converts each data type.
  These default mappings are described in the data types documentation for each connector.
  
  While the default mappings are generally sufficient, for some applications you might want to apply an alternate mapping.
  For example, you might need a custom mapping if the default mapping exports a column using the format of milliseconds since the UNIX epoch, but your downstream application can only consume the column values as formatted strings.
  You customize data type mappings by developing and deploying a custom converter.
  You configure custom converters to act on all columns of a certain type, or you can narrow their scope so that they apply to a specific table column only.
  The converter function intercepts data type conversion requests for any columns that match a specified criteria, and then performs the specified conversion.
  The converter ignores columns that do not match the specified criteria.
  
  Custom converters are Java classes that implement the Debezium service provider interface (SPI).
  You enable and configure a custom converter by setting the `converters` property in the connector configuration.
  The `converters` property specifies the converters avaialble to a connector, and can include sub-properties that further modify conversion behavior.
  
  After you start a connector, the converters that are enabled in the connector configuration are instantiated and are added to a registry.
  The registry associates each converter with the columns or fields for it to process.
  Whenever {prodname} processes a new change event, it invokes the configured converter to convert the columns or fields for which it is registered.
  
  // Type: assembly
  // Title: Creating a {prodname} custom data type converter
  // ModuleID: creating-a-debezium-custom-data-type-converter
  [id="implementing-a-custom-converter"]
  