State the difference between projecting and joining.
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- State the difference between projecting and joining.
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- Plot point please.5. calculate_new_balance Given a starting balance (a number), and a list of transaction tuples, calculate the final balance for an account. Transaction tuples are of the shape ("description", amount, "withdrawal") , or ("description", amount, "deposit"). The last entry in the tuple will be either "withdrawal" or "deposit". Every withdrawal decreases the balance of the account by the specified amount, and every deposit increases the balance. The return value is the new account balance, as a number. (which could be negative) Sample calls should look like: >>> calculate_new_balance(100, [("payday", 20, "deposit"), ("new shoes", 50, "withdrawal"), ("illicit winnings", 200, "deposit")]) 270 >>> calculate_new_balance (100, []) 100What are the differences between primary key, candidate key, and superkey?
- How do GROUP BY and HAVING clauses work with aggregate functions?Determine which of the following categories are represented in the existing book stock. Each category should only be included once.Database Question:In this problem, you will come up with decision trees to predict if a planet is habitable based only on features observed by the telescope.In the table below, you are given the data from all 800 planets surveyed so far. The features observed by telescope are Size (“Big” or “Small”), and Orbit (“Near” or “Far”). Each row indicates the values of the features and habitability, and how many times that set of values was observed. So, for example, there were 20 “Big” planets “Near” their star that were habitable.Determine if Planet=Big and Orbit=Far is habitable? Derive and draw the decision tree learned by ID3 on this data.