SQL help - forum topic by todil

Hi gurus, I am trying to generate a sql based on this scenario. please suggest how. i have a table with credit card number, transaction date and amount and merchant. I want to find a creditcard number which did transations in 3 consecutive months with same merchant with total amount >1000. eg:-a customer would have made transaction in walmart in oct, nov,dec and the total amount for 3 months should be > 1000. 

please suggest. 

Thanks