I need your help!!!.
I need to query a table in my database that has record of goods sold. I want the query to detect a particular product and also calculate the quantity sold. The product are 300 now, but it would increase in the future.
Below is a sample of my DB Table
I'm not exactly sure what your question is, but your table design seems to be your problem. Any time you have columns foo1, foo2, foo3, etc... that should be a sign to you that your design might need modification.
I suggest you look at database normalization and the Wikipedia page on First Normal Form. In particular you could look at the section about repeating groups across columns and how to resolve it.
You need to spend a couple hours learning about relational design. Model your entities (product, customer, order), create the necessary foreign keys and join tables and learn how to do joins in your queries.
Why do you have code, price, quantity, amount repeated 15 times in your table? try to look at Database Normalization :
I'm not sure which 'quantity' you need, as there are 12 different 'quantity' fields in your table. Here may be something akin to what you're looking for:
SELECT COUNT(quantity1) AS TotalAmnt
FROM litorder
WHERE product1 = 'yourProduct'
GROUP BY product1
You will want to try to normalize your database as well, to make queries like this easier in the future.
Since the table is not normalized, i think the query won't be neat. But if you have to do it the hard way then i think this might work
select product1,quantity1 from table name where product1 = 'product name you want to search' union select product2,quantity2 from table name where product2 = 'product name you want to search'
Make the above 15 times for every column in the table. But overtime as more products are added this query will become slow. So the best course is to normalize this table. That will surely save you tons of hours in future.