Last answered:

22 May 2023

Posted on:

14 May 2023

0

Resolved: Join and where used together

I couldn't understand the part in the video from minute 1:51 to 2:19

3 answers ( 3 marked as helpful)
Posted on:

22 May 2023

0

He said that its consider a good practice to include the column that act as a connection point between the tables (which is emp_no column from employees and salaries tables in this case ), and the column that show the condition of where clause (which is salary column from salaries table).


because you could only select (first_name, last_name) columns from first table and still get the same result.

Instructor
Posted on:

22 May 2023

0

Hi Fatma and Ahmed!
Thanks for reaching out.


@: Ahmed
Thanks for sharing this piece of information with the Community!

@: Fatma

As Ahmed said the instructor said that its considered a good practice to include the column which joins the tables and the one used in the WHERE clause.


Hope this helps.
Best,
Tsvetelin

Posted on:

22 May 2023

0

Thank you both for your help.

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