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  1. SQL
  2. SQL Practice
  3. Popular Websites For SQL Practice
  4. SQLZoo
  5. Teacher - Dept Tables

Using Null Quiz

Last updated 1 year ago

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  1. Select the code which uses an outer join correctly.

 SELECT teacher.name, dept.name 
 FROM teacher 
 LEFT OUTER JOIN dept 
 ON (teacher.dept = dept.id)
  1. Select the correct statement that shows the name of department which employs Cutflower

 SELECT dept.name 
 FROM teacher 
 JOIN dept ON (dept.id = teacher.dept) 
 WHERE teacher.name = 'Cutflower'
  1. Select out of following the code which uses a JOIN to show a list of all the departments and number of employed teachers

 SELECT dept.name, COUNT(teacher.name) 
 FROM teacher 
 RIGHT OUTER JOIN dept ON dept.id = teacher.dept 
 GROUP BY dept.name

4. Using SELECT name, dept, COALESCE(dept, 0) AS result FROM teacher on teacher table will: display 0 in result column for all teachers without department

5.Query:

SELECT name,
       CASE WHEN phone = 2752 THEN 'two'
            WHEN phone = 2753 THEN 'three'
            WHEN phone = 2754 THEN 'four'
            END AS digit
  FROM teacher

shows following 'digit':

'four' for Throd

6. Select the result that would be obtained from the following code:

 SELECT name, 
      CASE 
       WHEN dept 
        IN (1) 
        THEN 'Computing' 
       ELSE 'Other' 
      END 
  FROM teacher
Shrivell
Computing

Throd

Computing

Splint

Computing

Spiregrain

Other

Cutflower

Other

Deadyawn

Other

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