Update postgres doc about cdc publication (#13433)

* Update postgres doc about cdc publication

* Update wording

Author: tuliren

docs/integrations/sources/postgres.md

@@ -137,7 +137,11 @@ If you would like to use `wal2json` plugin, please change `pgoutput` to `wal2jso
 
 #### 5. Create publications and replication identities for tables
 
-For each table you want to replicate with CDC, you should add the replication identity \(the method of distinguishing between rows\) first. We recommend using `ALTER TABLE tbl1 REPLICA IDENTITY DEFAULT;` to use primary keys to distinguish between rows. After setting the replication identity, you will need to run `CREATE PUBLICATION airbyte_publication FOR TABLE <tbl1, tbl2, tbl3>;`. This publication name is customizable. **You must add the replication identity before creating the publication. Otherwise, `ALTER`/`UPDATE`/`DELETE` statements may fail if Postgres cannot determine how to uniquely identify rows.** Please refer to the [Postgres docs](https://www.postgresql.org/docs/10/sql-alterpublication.html) if you need to add or remove tables from your publication in the future.
+For each table you want to replicate with CDC, you should add the replication identity \(the method of distinguishing between rows\) first. We recommend using `ALTER TABLE tbl1 REPLICA IDENTITY DEFAULT;` to use primary keys to distinguish between rows. After setting the replication identity, you will need to run `CREATE PUBLICATION airbyte_publication FOR TABLE <tbl1, tbl2, tbl3>;`. This publication name is customizable. Please refer to the [Postgres docs](https://www.postgresql.org/docs/10/sql-alterpublication.html) if you need to add or remove tables from your publication in the future.
+
+Please note that:
+- You must **add the replication identity before creating the publication**. Otherwise, `ALTER`/`UPDATE`/`DELETE` statements may fail if Postgres cannot determine how to uniquely identify rows.
+- The publication should **include all the tables and only the tables that need to be synced**. Otherwise, data from these tables may not be replicated correctly.
 
 The UI currently allows selecting any tables for CDC. If a table is selected that is not part of the publication, it will not replicate even though it is selected. If a table is part of the publication but does not have a replication identity, that replication identity will be created automatically on the first run if the Airbyte user has the necessary permissions.