Hi. Could you please share what version you're using for flink and postgres-cdc?
I guess the two jar versions don't match. The source function has been (weakly) removed in flink 2.0. -- Best! Xuyang At 2025-07-11 12:26:30, "" <oh_...@nttdata-bizsys.co.jp> wrote: I need help to figure out the problem with sql-client. With postgres-cdc jar copied to lib and execute the following sql statements, got ClassNotFoundException. Error: Flink SQL> SELECT * FROM shipments; [ERROR] Could not execute SQL statement. Reason: java.lang.ClassNotFoundException: org.apache.flink.streaming.api.functions.source.SourceFunction Sql statements executed: Flink SQL> CREATE TABLE shipments ( > shipment_id INT, > order_id INT, > origin STRING, > destination STRING, > is_arrived BOOLEAN > ) WITH ( > 'connector' = 'postgres-cdc', > 'hostname' = 'localhost', > 'port' = '5432', > 'username' = 'postgres', > 'password' = 'postgres', > 'database-name' = 'postgres', > 'schema-name' = 'public', > 'table-name' = 'shipments', > 'slot.name' = 'flink', > -- experimental feature: incremental snapshot (default off) > 'scan.incremental.snapshot.enabled' = 'true' > ); [INFO] Execute statement succeeded. Flink SQL> SELECT * FROM shipments; [ERROR] Could not execute SQL statement. Reason: java.lang.ClassNotFoundException: org.apache.flink.streaming.api.functions.source.SourceFunction flink/lib: