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544 PointsCan anybody tell me why the answer is 6?
I just don't understand it's going to be 6
1 Answer
Steven Parker
231,236 PointsI 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?
SELECT FIRST_NAME, LAST_NAME, JOBS.*
FROM EMPLOYEES
JOIN JOBS ON EMPLOYEES.JOB_ID = JOBS.ID;
If you look at what is being SELECT
ed, 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 as
544 Pointsi as
544 PointsI misunderstood the concepts beforeοΌthank you for your explanation.