Question

Using both logical and boolean operators, construct a query statement that selects those counties with a population (pop) greater than 100,000, but only when median income (medinc) is below $20,000 per year.

a) SELECT * FROM Counties WHERE pop > 100,000 AND medinc < $20,000;
b) SELECT * FROM Counties WHERE pop < 100,000 OR medinc > $20,000;
c) SELECT * FROM Counties WHERE pop > 100,000 AND medinc > $20,000;
d) SELECT * FROM Counties WHERE pop < 100,000 AND medinc < $20,000;

Answer 1

The correct query statement is SELECT * FROM Counties WHERE pop > 100,000 AND medinc < $20,000; using the AND operator to meet both conditions.

Step-by-step explanation:

To construct a query that selects counties with a population greater than 100,000 and a median income below $20,000 per year, we need to use both logical and Boolean operators. Logical operators like AND are used to ensure that two conditions are true at the same time. Therefore, the correct query statement is:

SELECT * FROM Counties WHERE pop > 100,000 AND medinc < $20,000;

This statement will retrieve all records from the Counties table where the county population is more than 100,000 AND the median income is less than $20,000. It accurately uses the AND operator to connect both conditions ensuring that both criteria are met for the selected data.