How to increment update B table from A table on a daily basis

Question

hi ,
i have two table in two database,
Table A:
username
status
created
table B:
username
status
created
object_count
I want to insert everything from A to B. for example, on day 1, table A has 100 rows, then 100 rows will be inserted into B. on day 2, table A has 110 rows, then only the 10 new rows will be inserted.
i want to create a PL sql procedure, and create a shell script in cron job to call this procedure to update table B every day.
thanks for the help.
thanks.

Answer 1

thanks for the reply. i didn't state clear about my task. here is the detail of what exactly I am trying to do.
table USERACC_FOR_DOM_REP is acting a central repository table which will have all user information from all databases. I have 40+ database. of course , everyday new user will be added.
SQL> desc audadm.USERACC_FOR_DOM_REP
Name Null? Type
USERNAME NOT NULL VARCHAR2(30)
ACCOUNT_STATUS NOT NULL VARCHAR2(32)
LOCK_DATE DATE
EXPIRY_DATE DATE
CREATED NOT NULL DATE
PROFILE NOT NULL VARCHAR2(30)
TARGET_DB VARCHAR2(9)
TARGET_NODE VARCHAR2(64)
INSERT_DATE DATE
OBJECT_COUNT NUMBER
i can create shell script, loop through each database, and use below SQL to update the USERACC_FOR_DOM_REP table on the daily basis. but the problem is that duplicated entry will be created every day. I only need to insert any new users which added in dba_users table.
i guess i need a PL SQL procedure to check if a username already exist in table USERACC_FOR_DOM_REP, and that user come from the same database.
insert into USERACC_FOR_DOM_REP
select username, account_status, lock_date, expiry_date, a.created, profile,
name as target_db, host_name as target_node, sysdate as insert_date,
(select count(*) from dba_objects where OWNER=a.username) as object_count
from dba_users a, v$database, v$instance;