Question at position 9 Which of the following questions is answered by the SQL statement? SELECT COUNT (Product_Description) FROM Product_T;How many characters are in the field name "Product_Description"?How many products are in the table Product_T?How many different columns named "Product_Description" are there in table Product_T?How many products have product descriptions in the Product Table?

Question

Question at position 9 Which of the following questions is answered by the SQL statement? SELECT COUNT (Product_Description) FROM Product_T;How many characters are in the field name "Product_Description"?How many products are in the table Product_T?How many different columns named "Product_Description" are there in table Product_T?How many products have product descriptions in the Product Table?

BlackTom AI · Accepted Answer

The prompt presents a SQL query: SELECT COUNT (Product_Description) FROM Product_T; and asks which question this query answers. We need to evaluate what COUNT(column) returns versus the other possible questions.

Option 1: 'How many characters are in the field name "Product_Description"?' This is about the length of the column name string itself. SQL in this form does not inspect metadata like the length of the column name; it operates on data within the table. Therefore, this option is incorrect.

Option 2: 'How many products are in the table Product_T?' If you wanted the total number of rows (products) regardless of content, you would typically use COUNT(*) or COUNT(1). COUNT(Product_Description) specifically counts non-null entries in the Product_Description column, not all rows. Thus, this option is not what the query returns.

Option 3: 'How many different columns named "Product_Description" are there in table Product_T?' This concerns the schema—how many columns exist with that name. In a well-formed table, a column name appears only once; also, the query does not query metadata about the schema. So this interpretation is incorrect.

Option 4: 'How many products have product descriptions in the Product Table?' This directly aligns with COUNT(Product_Description). COUNT(column) tallies the number of rows where the specified column is not NULL. Therefore, it answers how many products possess a non-empty product description in the Product_T table, which is a precise restatement of this option.

In summary, the only option that matches the behavior of counting non-null values in the Product_Description column is the last one. The other options describe different questions that would require different SQL constructs or address metadata rather than row data.

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