1-api and database transactions limit for data comming default is 500 row and client can chage it but cant exceed max value which is 1000

2- api should contain limit parameter and we will suppose every api 
has limit and if api running and data come back exceed 1000 row 
stop this operation from working and send notification about that 
to admin and this client

first_id  last_id created_at updated_at lastUpdateModifed

3- when create data from one => two take data from one and check id of first website if exists in middle database(first_id) pass this row (continue without doing nothing)
if not exist (first_id) in middle database ==> create new row


update or create ask user what time want to check update (last day , last hour,etc) to order data based on time 

and finally ask user what time want to work this cron (every minute , every hour , etc) 

and based on time order data coming based on this time
and check first_id with lastupdateModified is equal to updated_of of first website id or not if equal dont make anything if changed 
updated new data from first website to second website and update lastUpdateModied


start_date & end_date


and check create and update from one to second and second to one

and ask user if website want to create and update into second 
or from second into one or twice