here is a postgresql backed cdc table create that i use.

CREATE OR REPLACE TABLE accountholders (
     _id                BIGINT                  NOT NULL
    ,nationalid         VARCHAR(16)             NOT NULL
    ,firstname          VARCHAR(100)
    ,lastname           VARCHAR(100)
    ,dob                VARCHAR(10) 
    ,gender             VARCHAR(10)
    ,children           INT
    ,address            STRING
    ,accounts           STRING
    ,emailaddress       VARCHAR(100)
    ,mobilephonenumber  VARCHAR(20)
    ,created_at         TIMESTAMP_LTZ(3)
    ,WATERMARK          FOR created_at AS created_at - INTERVAL '15' SECOND
    ,PRIMARY KEY (_id) NOT ENFORCED
) WITH (
     'connector'                           = 'postgres-cdc'
    ,'hostname'                            = 'postgrescdc'
    ,'port'                                = '5432'
    ,'username'                            = 'dbadmin'
    ,'password'                            = 'dbpassword'
    ,'database-name'                       = 'demog'
    ,'schema-name'                         = 'public'
    ,'table-name'                          = 'accountholders'
    ,'slot.name'                           = 'accountholders_pyflink'           -- Can't include capital letters
    ,'scan.incremental.snapshot.enabled'   = 'true'               
    ,'scan.startup.mode'                   = 'initial'            
    ,'decoding.plugin.name'                = 'pgoutput'
    ,'scan.incremental.snapshot.chunk.size' = '4096'    -- Explicitly set chunk size
    ,'scan.snapshot.fetch.size'             = '512'     -- Add fetch size
    ,'connect.timeout'                      = '30s'     -- Add connection timeout
);