# Kafka Connect ExtractNewRecordState (Debezium) SMT Usage Reference for Confluent Cloud The `ExtractNewRecordState` SMT (`io.debezium.transforms.ExtractNewRecordState`) flattens Debezium change events by replacing the event envelope with the row state after the change. ## Description Debezium change events use a nested envelope with `before`, `after`, `source`, `op`, and `ts_ms` fields. Use this SMT when downstream consumers or sink connectors require a flat record instead of the envelope. In addition to unwrapping the `after` state, you can configure this SMT to: * Control how delete events and tombstones are emitted. * Copy change event metadata into the record value or headers. * Replace null column values with their column default values. For complete details, see the official Debezium [New Record State Extraction](https://debezium.io/documentation/reference/stable/transformations/event-flattening.html) documentation. For the full list of available SMTs, see [Kafka Connect Single Message Transformation Reference for Confluent Cloud](overview.md#connect-transforms-supported). #### NOTE When using this SMT, consider the following: - Place this SMT after SMTs that read the change event envelope, such as [ExtractChangedRecordState](extractchangedrecordstate.md#extractchangedrecordstate), and before SMTs that operate on the flattened row fields. The record key and headers set by earlier SMTs, such as [ToLogicalTopicRouter](tologicaltopicrouter.md#tologicaltopicrouter), are preserved. - Don’t use `unwrap` as the transform alias for the managed Debezium change data capture (CDC) Source connectors. The connector reserves this alias for `after.state.only`. For details, see [Transform alias validation](../single-message-transforms.md#cc-single-message-transforms-transform-alias-validation). - If you set `after.state.only` to `true`, the connector already flattens records, so the options of this SMT have no effect. Set `after.state.only` to `false` to configure this SMT. - `replace.null.with.default` applies only to columns that have a default value defined in the source database. Null values in columns without a default remain null. ## Limitations The `ExtractNewRecordState` SMT is available only for the Oracle XStream CDC Source connector and for managed Debezium CDC Source connectors, such as PostgreSQL, MySQL, SQL Server, and MariaDB. For the Oracle XStream CDC Source connector, `after.state.only` doesn’t flatten records, and the `unwrap` alias isn’t reserved. To flatten records, add this SMT to the connector configuration. ## Properties The following table lists the configuration options for the `ExtractNewRecordState` SMT. | Name | Description | Type | Default | Importance | |----------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------|-----------|--------------| | `delete.tombstone.handling.mode` | How to handle delete events and tombstones. Accepts `drop`,
`tombstone`, `rewrite`, `rewrite-with-tombstone`, or
`delete-to-tombstone`. Replaces `delete.handling.mode` and
`drop.tombstones`. If you don’t set this option, the SMT uses
`delete.handling.mode` and `drop.tombstones`. | string | | medium | | `delete.handling.mode` | Deprecated. Use `delete.tombstone.handling.mode` instead. How to
handle delete events. Accepts `none`, `drop`, or `rewrite`. | string | `drop` | medium | | `drop.tombstones` | Deprecated. Use `delete.tombstone.handling.mode` instead. Whether to
drop tombstone records from the stream. | boolean | `true` | low | | `route.by.field` | The name of a field in the row state whose value replaces the record’s
topic name. | string | | low | | `add.fields` | A comma-separated list of change event metadata fields, such as `op`,
`table`, or `source.ts_ms`, to add to the record value. | list | | low | | `add.fields.prefix` | The prefix added to the names of fields added by `add.fields`. | string | `__` | low | | `add.headers` | A comma-separated list of change event metadata fields to add to the
record headers. | list | | low | | `add.headers.prefix` | The prefix added to the names of headers added by `add.headers`. | string | `__` | low | | `replace.null.with.default` | Whether to replace a null column value with the default value defined
for the column in the source database. | boolean | `true` | low | ## Example The following example flattens change events, rewrites delete events with a `__deleted` field, and adds the operation type to the record value. The example assumes that `after.state.only` is `false`, if the connector has that property. ```json "transforms": "flatten", "transforms.flatten.type": "io.debezium.transforms.ExtractNewRecordState", "transforms.flatten.delete.tombstone.handling.mode": "rewrite", "transforms.flatten.add.fields": "op" ``` ## Predicates Transformations can be configured with *predicates* so that the transformation is applied only to records which satisfy a condition. You can use predicates in a transformation chain and, when combined with the [Kafka Connect Filter (Kafka) SMT Usage Reference for Confluent Cloud](filter-ak.md#ak-filter), predicates can conditionally filter out specific records. For details and examples, see [Predicates](filter-ak.md#predicates).