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Databases SQL Reporting by Example Orientation: Selecting Data Orientation Quiz

Can anybody tell me why the answer is 6?

I just don't understand it's going to be 6

1 Answer

Steven Parker
Steven Parker
229,582 Points

I assume you're asking about this question:

The EMPLOYEES table has 23 columns and the JOBS table has 4. How many COLUMNS does the following query return?


If you look at what is being SELECTed, you'll see that it is FIRST_NAME, LAST_NAME, and JOBS.* which means "everything from JOBS". So that's 2 name columns, and all 4 columns from JOBS, for a total of 6. Make sense now?

I misunderstood the concepts before,thank you for your explanation.