用flinkcdc同步pg库，我的postgre表明明有主键，为啥还会报这个错啊

java.lang.IllegalStateException: The "before" field of UPDATE/DELETE message is null, please check the Postgres table has been set REPLICA IDENTITY to FULL level. You can update the setting by running the command in Postgres 'ALTER TABLE public.afin_bill_task REPLICA IDENTITY FULL'. Please see more in Debezium documentation: https://debezium.io/documentation/reference/1.5/connectors/postgresql.html#postgresql-replica-identity at com.ververica.cdc.connectors.postgres.table.PostgresValueValidator.validate(PostgresValueValidator.java:46) at com.ververica.cdc.debezium.table.RowDataDebeziumDeserializeSchema.deserialize(RowDataDebeziumDeserializeSchema.java:132) at com.ververica.cdc.debezium.internal.DebeziumChangeFetcher.handleBatch(DebeziumChangeFetcher.java:229) at com.ververica.cdc.debezium.internal.DebeziumChangeFetcher.runFetchLoop(DebeziumChangeFetcher.java:163) at com.ververica.cdc.debezium.DebeziumSourceFunction.run(DebeziumSourceFunction.java:446) at org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:110) at org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:67) at org.apache.flink.streaming.runtime.tasks.SourceStreamTask$LegacySourceFunctionThread.run(SourceStreamTask.java:323)