1. get customerid,totalamt,noOfinstallements for every customer.
customerid,installmentdate,installmentamt 1,2020-01-01,100 1,2020-02-01,150 2,2020-01-01,100 2,2020-02-01,100 2,2020-03-01,100 2,2020-04-01,100 op: customerid,totalamt,noOfinstallements 1,250,2 2,400,4
Ans.
select custid, sum(installmentamt) as totalamt, count(custid) as noofinstallements from cust_tbl group by custid
2. get  latest record for every order_id.
order_id,order_status,order_time 1,Ordered,03-Jan 1,Shipped,05-Jan 2,Ordered,03-Jan 2,Shipped,05-Jan 2,Delivered,10-Jan op: 1,Shipped,05-Jan 2,Delivered,10-Jan

3. get percentage in a hike for every emp_id

emp_id,emp_name,emp_sal,ts 1,Ravi,100,03-Jan-2018 1,Ravi,120,03-Jan-2019 1,Ravi,140,03-Jan-2020 2,Ram,110,10-Jan-2016 2,Ram,140,10-Jan-2017 2,Ram,160,10-Jan-2018

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