SQL.md

Write a query to get the first and last record from a table

select * from Student where RowID = select max(RowID) from Student;
select * from Student where RowID = select min(RowID) from Student; -- or select * from Student where Rownum = 1;
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dislay first 10 records

select * from Student where Rownum <= 10; -- or select top 10 * from Student;
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create table like copy

Create table Student2 as Select * from Student;
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hirarchy code

WITH Employee_CTE(employeeid,hierarchy_level,name) AS
(
SELECT employeeid,1 as level,name from employee where employeeid=1
UNION ALL
SELECT e.employeeid,level +1, e.name
from employee e
INNER JOIN Employee_CTE c ON e.employeeid = c.managerid
)
SELECT * FROM Employee_CTE order by employeeid

https://www.w3schools.com/sql/

https://upesonline.ac.in/blog/advanced-sql-interview-questions