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Bug report

Debezium Server 

Data duplication problem using postgresql source on debezium server.

When debezium server is executed for the second time, the data of the last transaction comes in once again. From the 3rd run onwards it is normal.

case1 )

1) Create a table in postgresql.
2) Load 5 rows of data with the Copy command.
3) Execute cdc job with debezium server.
4) Row 5 comes in with opcode "r".
5) Stop the debezium server.
6) Run the debezium server again.
7) Row 5 comes in with opcode "c".   <= Duplicate data.( snapshot data )
8) Stop the debezium server.
9) Run the debezium server again.
10) No data coming in.  ( Noraml )

case2 ) 

1) Create a table in postgresql.
2) Load 5 rows of data with the Copy command.
3) One additional row is loaded with SQL.
3) Execute cdc job with debezium server.
4) Row 6 comes in with opcode "r".
5) Stop the debezium server.
6) Run the debezium server again.
7) Row 1 comes in with opcode "c".   <= Duplicate data. ( insert data )
8) Stop the debezium server.
9) Run the debezium server again.
10) No data coming in.  ( Noraml )

What Debezium connector do you use and what version?

Debezium Server : 1.8.1 final and 1.9.1 final 

What is the connector configuration?

debezium.source.connector.class=io.debezium.connector.postgresql.PostgresConnector
debezium.source.offset.storage.file.filename=data/job1-offset.dat
debezium.source.offset.flush.interval.ms=0
debezium.source.database.hostname=localhost
debezium.source.database.port=15432
debezium.source.database.user=user
debezium.source.database.password=password
debezium.source.database.dbname=testdb
debezium.source.database.server.name=postgre-job1
debezium.source.schema.include.list=public
debezium.source.table.include.list=public.housing_ny_sample
debezium.source.max.queue.size=8192
debezium.source.max.batch.size=2048
debezium.source.snapshot.mode=initial

What is the captured database version and mode of depoyment?

debezium-postgresql:1.9

What behaviour do you expect?

I hope there are no duplicate events coming in.

What behaviour do you see?

When debezium server is executed for the second time, the data of the last transaction comes in once again. From the 3rd run onwards it is normal.

Do you see the same behaviour using the latest relesead Debezium version?

Both 1.8.1 and 1.9.1 are the same.

In Mysql, that doesn't happen. It only happens in Postgresql.
Do you have any additional settings?