Connectors can be configured with transformations to make lightweight per message modifications. {prodname} provides several link:{link-kafka-docs}/#connect_transforms[single message transformations] (SMTs) that you can use to either modify records before they are sent to Apache Kafka (by applying them to the {prodname} connectors), or when they are read from Kafka by a sink connector. Also xref:{link-debezium-server}[{prodname} Server] supports the usage of SMTs.
|Extracts the flat structure of field names and values from Debezium change events, facilitating sink connectors which cannot process Debezium's complex event structure.
|Applies a filter to the change events emitted by the connectors, based on their content. This lets you propagate only those records that are relevant to you.
By means of xref:transformations/applying-transformations-selectively.adoc[SMT Predicates] you can apply any of the transformations selectively, so that it modifies only that subset of change event messages that share a common characteristic.
Most of the above SMTs are available by default with the {prodname} container image, but you need to opt-in for the scripting-based ones (Message Filtering or Content-based Routing). See the link:https://github.com/debezium/container-images/tree/main/connect/1.7#enable_debezium_scripting[README] file of the container image for more details.