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Databases

Fredric von Stange
Fredric von Stange
3,867 Points
Posted by Fredric von Stange
Fredric von Stange
3,867 Points

My SQL query using a derived table

SQL Reporting by Example > A Smelly Issue

I came up with a way to answer this problem using a derived table. Check it out:

SELECT COUNT(*) FROM SUBJECTS

  INNER JOIN (SELECT * FROM CLASSES WHERE PERIOD_ID = 1) AS PE_FIRST
    ON PE_FIRST.SUBJECT_ID = SUBJECTS.ID

  INNER JOIN SCHEDULE 
    ON SCHEDULE.CLASS_ID = PE_FIRST.ID

WHERE NAME LIKE "physical education";