Following type of SQL’s can cause “subquery in FROM must have an alias” issue. They are like below,
ERROR: subquery in FROM must have an alias Hint: For example, FROM (SELECT ...) [AS] foo.
It needs to be fixed to meet the SQL standards. There is no question asked about why PostgreSQL did not support 🙂 why should I create alias in all the cases 🙂
select * from (SELECT student_id, status from student where dep_id=1001 limit 2)
The correct query with alias are as follows,
select * from (SELECT student_id, status from student where dep_id=1001 limit 2) as std
For more reference refer following link,
Also in my experience tools like pganalyzer can come handy for analysing such queries failing at the server side. Good thing about this tool is it provide fix recommendation 🙂