I have a project I am working on that requires the following : create a normalized sample rdbms (5 tables) using Java I entered 1 million rows of data to each table run two OLTP and two OLAP queries on the normalized tables. Denormalized tables. run the same OLTP and OLAP queries on them and compare time. What does OLAP query mean? I've searched the internet and all that I can find is that I have to make a cube, and apply queries on it. How can I write an OLAP query on a RDBMS? I have a sample : tables normalized(orders,product,customer,branch,sales) sales : order_id,product_id,quantity product : product_id,name,description,price,sales_tax customer : customer_id,f_name,l_name,tel_no,addr,nic,city branch : branch_id,name,tel_no,addr,city orders : order_id,customer_id,order_date,branch_id I want to write an OLAP query on the above tables. I am using Oracle Express with SQL Developer.