Find most recent Status for each Employee, based on annual updates - sql

I have a problem with a query.
I have one table named EMPLOYEE and there i have the fields NAME, YEAR and STATUS.
Every employee can have several years and several status but I need the status of the most recent year.
How can I get that data?

This should do it:
SELECT e.[Name],
e.[Year],
e.[Status]
FROM employee AS e
INNER JOIN
(
SELECT [Name],
MAX([Year])
FROM employee
GROUP BY [Name]
) AS m ON e.[Name] = m.[Name]
AND e.[Year] = m.[Year];

Related

SQL select groups where values are exclusively in a list

Given a table with two columns, department and employee, where every employee belongs to 1 department.
Given a list of employee ids, how do I select departments where all employees are in the list?
Department
Employee
finance
1
finance
2
marketing
3
marketing
4
IT
5
IT
6
given (2,3,4,5,6), returns ('marketing', 'IT')
(Note: DB flavor does not matter to me, you may use standard or DB-specific SQL)
Put your input id's into a table, join to the existing table, and check counts between input and the existing employees. If they match, output.
Change this to whatever RDBMS you're using
CREATE TEMP TABLE input_vals (id int);
insert into input_vals
values
(2),
(3),
(4),
(5),
(6);
with cte_joins AS (
select ot.department,
count(ot.employee) AS employee_count1,
sum(case when iv.id is not null then 1 else 0 end) AS employee_count2
from orig_table ot
left join input_vals iv
on ot.employee = iv.id
group by ot.department
)
select department
from cte_joins
where employee_count1 = employee_count2
You can use a couple of derived tables - one to get the count of employees in each department and one to get the count of employees in each department limited by your list of employees. Return the ones that match.
select
distinct full_list.department
from (
select
department,
count (*) as cnt
from
<your table>
group by department) full_list
inner join (
select
department,
count (*) as cnt
from
<your table>
group by department
where
employee in (2,3,4,5,6)
) limited_list
on full_list.department = limited_list.department
and full_list.cnt = limited_list.cnt
-- departments
select department from t where employee in (2,3,4,5,6);
-- departments containing extra persons
select department from t
where department in (select department from t where employee in (2,3,4,5,6))
and employee not in (2,3,4,5,6);
--- departments, employees from the list, with no extra
select department from t
where employee in (2,3,4,5,6) and department not in (
select department from t
where department in (
select department from t where employee in (2,3,4,5,6)
) and employee not in (2,3,4,5,6)
)
Assume you employee list is captured as a column in a table. Since you didn't provide any detail on the tool set you are using.
Something like this is a common pattern, depending on your dbms there's other more simple syntax.
select distinct
de.department
from department_employee de
where not exists
( select 1
from department_employee de2
where not exists
( select 1
from employee_list el
where de2.employee = el.employee
)
and de.department = de2.department
);

SQL Server Group Records Based Another Columns

I am working on a table that contains employee data. The table has historical employee records based on department and year as follows:
Now I want to consolidate records based on EmployeeId, Department and get the Min FromYear and Max ToYear like this:
I tried to use a query :
Select EmployeeId, Department, MIN(FromYear), MAX(ToYear)
from Employee
GROUP BY EmployeeId, Department
But this query fails for the employee with ID 3 as it returns me only 2 rows:
I have added a similar structure and query here: http://sqlfiddle.com/#!9/6f1e53/5
Any help would be highly appreciated!
This is a gaps-and-islands problem. Identify the islands using lag() and a cumulative sum. Then aggregate:
select employeeid, department, min(fromyear), max(toyear)
from (select e.*,
sum(case when prev_toyear >= fromyear - 1 then 0 else 1 end) over (partition by employeeid order by fromyear) as grp
from (select e.*,
lag(toyear) over (partition by employeeid, department order by fromyear) as prev_toyear
from employee e
) e
) e
group by employeeid, department, grp
order by employeeid, min(fromyear);
Here is a db<>fiddle.
you can use self join as well
select a.employeeid, min(a.fromyear), max(b.toyear) from emp a
inner join emp b on a.employeeid=b.employeeid
group by a.employeeid

SQL Select the highest sale for the current month

I am trying to Select the name, email address that has the highest individual sale for the current month but for some reason my select statement won't return the right date or the highest amount. Any guidance or help on right direction would be appreciated
Select
FirstName, LastName,Email, SaleDate, Max(Total)as HighestTotal
From
Sale, Employee
where
month(SaleDate) = 12
Group by
SaleDate, FirstName, LastName, Email
Use TOP 1 with ORDER BY HighestTotal desc to get the highest individual sale for the given month
Also use proper INNER JOIN syntax to join two tables. Considering that both the tables have emp_id as common column
SELECT TOP 1 WITH ties E.FirstName,
E.LastName,
E.Email,
S.SaleDate,
S.Total AS HighestTotal
FROM Sale S
INNER JOIN Employee E
ON E.emp_id = S.Emp_id
WHERE Month(S.SaleDate) = 12
ORDER BY HighestTotal DESC
With Ties will bring more than one employee in case of tie in highest individual sale.
1) You have to add a condition for the current year:
where month( SaleDate) = 12 AND year(SaleDate) = 2015
2) You have to add ORDER BY to get the highest value:
ORDER BY HighestTotal DESC
LIMIT 1

SQL Server more columns than group by

I have the following example tables
Employee (EmpID, DepID)
Order (OrderID, EMpID, description)
What I'm trying to achieve is to select employees with most orders by department. I'm on it for like 4 hours already and can't find resolution to this perhaps easy problem.
All I get is either number of order by employee or max number of orders by one employee in one department but I'm struggling to get result as:
DepID, EmpID, Number of orders
Here's my solution for you :
WITH Temp AS (
SELECT
emp.EMpID
,emp.DepID
,COUNT(OrderId) nb_order
,ROW_NUMBER() OVER(PARTITION BY emp.DepID ORDER BY COUNT(OrderId) DESC) Ordre
FROM
Order ord
INNER JOIN
Employee emp
ON emp.EmpID = ord.EmpID
GROUP BY
emp.EMpID
,emp.DepID)
SELECT *
FROM Temp
WHERE Ordre = 1
I hope this will help you :)

How to write a query to get the latest employee record given the effective date in oracle?

I have a employee and employee_history table. For every update on employee table, I insert a record into the employee_history table.
Both the tables have a column called as effective date which indicates that the employee status as on that effective date.
Below are my two tables.
I need to get the employee record latest as on that effective date.
e.g If I need to get the employee as on 16 may I should get the emp_hist_id = 2 record from history table. As on 5 june I should get the emp_hist_id = 4 from hist table.
And as on 15th August I should get the record from employee table itself.
Please help.
You could try something like
SELECT * FROM (
SELECT * FROM (
(SELECT emp_id, name, email, title, region, division, "effective date"
FROM employee
WHERE emp_id = desired_id)
UNION
(SELECT emp_id, name, email, title, region, division, "effective date"
FROM employee _history
WHERE emp_id = desired_id)
) t
WHERE t."effective date" <= desired_date
ORDER by t."effective date" DESC) p
WHERE ROWNUM = 1
The idea is to take records related to desired user from both tables, then take dates lower than desired one and finally catch the first
You can solve this problem without analytic functions. The subquery here calculates the most recent effective date in the history record before the employee effective date:
select e.*
from employee_history eh join
(select e.employee_id, max(eh.effective_date) as latest_effective_date
from employee e join
employee_history eh
on e.employee_id = eh.employee_id and
e.effective_date >= eh.effective_date
) ehl
on eh.employee_id = ehl.employee_id and
eh.effective_date = ehl.effective_date
This solution assumes that there are no duplicate effective dates in the history table. If there are, then you have another option. Assuming the employee_history_ids are assigned sequentially, take the max of that id instead of the date.
There are alternative formulations of the solution using Oracle's analytic functions.
Try the following :
SELECT *
FROM
(SELECT e.emp_id,
e.name,
e.email,
e.title,
e.region,
e.division,
e.effective_date,
row_number() over (partition BY e.emp_id
ORDER BY e.effective_date DESC) rn
FROM employee e
UNION ALL
SELECT eh.emp_id,
eh.name,
eh.email,
eh.title,
eh.region,
eh.division,
eh.effective_date,
row_number() over (partition BY eh.emp_id
ORDER BY eh.effective_date DESC) rn
FROM employee_history eh)
WHERE effective_date < to_date('15/06/2012','DD/MM/YYYY')
AND rn = 1
you can see a better example here