A database question encountered during the interview and a database encountered during the interview

A database question encountered during the interview and a database encountered during the interview

I have interviewed many organizations over the past few days and made some pen-related questions. I will recall and sort them out.

The following is a list of problems

What impressed me today is a database operation question.

Question: There are three tables, which are required to query the eid and ename of all employees who [job development only]

At first, I felt very simple. I wrote the following SQL statement into it.

Select eid, ename from emp where eid not in (select eid from ej where jid = (select jid from job where jname = 'test '));

Later I thought it would be right, but what if there are three or more positions?

For example

The original statement is obviously not applicable.

Then I found another method.

Select eid, ename from emp where eid not in (select eid from ej where jid in (select jid from job where jname <> 'developing '));

The query result is correct! But...

I used two subqueries to reduce the efficiency of SQL statements. Is there a better way?

Here, I also hope to get your suggestions and see if there is a better answer!

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