Q740
What will be the result of the following MySQL command? WHERE end_date IS NULL AND (title=’teller’ OR start_date < ‘2007-01-01’)
A.
Only those rows will be selected whose" end_date" should be NULL
AnswerB.
Only those rows are selected whose "TITLE" should be 'teller'
C.
Only those employee will be selected who joined the organisation prior to 2007
D.
All of the mentioned
Answer: Option A
Solution
Answer: Option A
Solution:
This MySQL command is used to filter rows from a table based on conditions related to "end_date", "title", and "start_date". Let's break down the command:
* WHERE end_date IS NULL: This part selects rows where the "end_date" column is NULL. It means that the value in the "end_date" column is empty or unknown.
* AND (title=’teller’ OR start_date < ‘2007-01-01’): This part uses the AND operator to combine two conditions. Let's further break down this part: * title=’teller’: This condition selects rows where the "title" column is equal to 'teller'. * OR start_date < ‘2007-01-01’: This condition selects rows where the "start_date" column is before '2007-01-01'.
In summary, the command will select rows that meet both conditions:
* The "end_date" must be NULL. * Either the "title" is 'teller', OR the "start_date" is before '2007-01-01'.
Therefore, the correct answer is Option D: All of the mentioned.
The command will select rows that meet any of these criteria:
* Employees with a NULL "end_date" and the title 'teller'. * Employees with a NULL "end_date" and a start date before '2007-01-01'.