I have the current database schema
EMPLOYEES
ID | NAME | JOB
JOBS
ID | JOBNAME | PRICE
I want to query so that it goes through each employee, and gets all their jobs, but I want each employee ID to be grouped so that it returns the employee ID followed by all the jobs they have. e.g if employee with ID 1 had jobs with ID, JOBNAME (1, Roofing), (1,Brick laying)
I want it to return something like
1 Roofing Bricklaying
I was trying
SELECT ID,JOBNAME FROM JOBS WHERE ID IN (SELECT ID FROM EMPLOYEES) GROUP BY ID;
but get the error
not a GROUP BY expression
Hope this is clear enough, if not please say and I'll try to explain better
EDIT:
WITH ALL_JOBS AS
(
SELECT ID,LISTAGG(JOBNAME || ' ') WITHIN GROUP (ORDER BY ID) JOBNAMES FROM JOBS GROUP BY ID
)
SELECT ID,JOBNAMES FROM ALL_JOBS A,EMPLOYEES B
WHERE A.ID = B.ID
GROUP BY ID,JOBNAMES;
In the with clause, I am grouping by on ID and concatenating the columns corresponding to an ID(also concatenating with ' ' to distinguish the columns).
For example, if we have
ID NAME
1 Roofing
1 Brick laying
2 Michael
2 Schumacher
we will get the result set as
ID NAME
1 Roofing Brick laying
2 Michael Schumacher
Then, I am join this result set with the EMPLOYEES table on ID.
You need to put JobName to group by expression too.
SELECT ID,JOBNAME FROM JOBS WHERE ID IN (SELECT ID FROM EMPLOYEES) GROUP BY ID,JOBNAME;
Related
I looked at other examples, but I don't know enough about SQL to adapt it to my needs. I have a table that looks like this:
ID Month NAME COUNT First LAST TOTAL
------------------------------------------------------
1 JAN2013 fred 4
2 MAR2013 fred 5
3 APR2014 fred 1
4 JAN2013 Tom 6
5 MAR2014 Tom 1
6 APR2014 Tom 1
This could be in separate queries, but I need 'First' to equal the first month that a particular name is used, so every row with fred would have JAN2013 in the first field for example. I need the 'Last" column to equal the month of the last record of each name, and finally I need the 'total' column to be the sum of all the counts for each name, so in each row that had fred the total would be 10 in this sample data. This is over my head. Can one of you assist?
This is crude but should do the trick. I renamed your fields a bit because you are using a bunch of "RESERVED" sql words and that is bad form.
;WITH cte as
(
Select
[NAME]
,[nmCOUNT]
,ROW_NUMBER() over (partition by NAME order by txtMONTH ASC) as 'FirstMonth'
,ROW_NUMBER() over (partition by NAME order by txtMONTH DESC) as 'LastMonth'
,SUM([nmCOUNT]) as 'TotNameCount'
From Table
Group by NAME, [nmCOUNT]
)
,cteFirst as
(
Select
NAME
,[nmCOUNT]
,[TotNameCount]
,[txtMONTH] as 'ansFirst'
From cte
Where FirstMonth = 1
)
,cteLast as
(
Select
NAME
,[txtMONTH] as 'ansLast'
From cte
Where LastMonth = 1
Select c.NAME, c.nmCount, c.ansFirst, l.ansLast, c.TotNameCount
From cteFirst c
LEFT JOIN cteLast l on c.NAME = l.NAME
Say I have a table A that contains a list of a potential employees ID's and their professional skills in the form of a skill code:
ID | skill code
005 12
005 3
007 42
007 8
013 6
013 22
013 18
And I have another table B that lists several job position ID's and their corresponding required skill ID's:
Job ID | skill code
1 3
1 32
1 21
1 44
2 15
2 62
.
.
.
How can I find out which Job Id's a specific person is qualified for? I need to select all Job Id's that contain all the person's skills. Say for instance I need to find all job ID's that employee ID 003 is qualified for, how would I structure an Oracle SQL query to get this information?
I want to be able to enter any employee ID in a WHERE clause to find what jobs that person is qualified for.
An idea would be to count the number of skills for every person and job:
SELECT A.id as person_id,
B.JOB_ID
FROM A
JOIN B
ON A.skill_code=B.skill_code
GROUP BY a.id, b.job_id
HAVING count(*) = (select count(*) from b b2 where b2.job_id = b.job_id);
Not tested and assuming that tables are well normalized.
UPDATE after the OP's comment.
It is asked for all the jobs which necessitate all skills of a person:
SELECT A.id as person_id,
B.JOB_ID
FROM A
JOIN B
ON A.skill_code=B.skill_code
GROUP BY a.id, b.job_id
HAVING count(*) = (select count(*) from a a2 where a2.job_id = b.job_id);
Update2: The question was updated with:
I want to be able to enter any employee ID in a WHERE clause to find what jobs that person is qualified for.
For this, you just add WHERE a.id = :emp_id to the first query. (above group by)
Try this one
WITH b1 AS
(SELECT job_id,
skill,
COUNT(*) over (partition BY job_id order by job_id) rr
FROM b
) ,
res1 AS
(SELECT a.id,
b1.job_id,
rr,
COUNT(*) over (partition BY id, job_id order by id) rr2
FROM A
JOIN B1
ON A.skill=B1.skill
)
SELECT id, job_id FROM res1 WHERE rr=rr2
Heres my scenario.
I have a table with 3 rows I want to return within a stored procedure, rows are email, name and id. id must = 3 or 4 and email must only be per user as some have multiple entries.
I have a Select statement as follows
SELECT
DISTINCT email,
name,
id
from table
where
id = 3
or id = 4
Ok fairly simple but there are some users whose have entries that are both 3 and 4 so they appear twice, if they appear twice I want only those with ids of 4 remaining. I'll give another example below as its hard to explain.
Table -
Email Name Id
jimmy#domain.com jimmy 4
brian#domain.com brian 4
kevin#domain.com kevin 3
jimmy#domain.com jimmy 3
So in the above scenario I would want to ignore the jimmy with the id of 3, any way of doing this without hard coding?
Thanks
SELECT
email,
name,
max(id)
from table
where
id in( 3, 4 )
group by email, name
Is this what you want to achieve?
SELECT Email, Name, MAX(Id) FROM Table WHERE Id IN (3, 4) GROUP BY Email;
Sometimes using Having Count(*) > 1 may be useful to find duplicated records.
select * from table group by Email having count(*) > 1
or
select * from table group by Email having count(*) > 1 and id > 3.
The solution provided before with the select MAX(ID) from table sounds good for this case.
This maybe an alternative solution.
What RDMS are you using? This will return only one "Jimmy", using RANK():
SELECT A.email, A.name,A.id
FROM SO_Table A
INNER JOIN(
SELECT
email, name,id,RANK() OVER (Partition BY name ORDER BY ID DESC) AS COUNTER
FROM SO_Table B
) X ON X.ID = A.ID AND X.NAME = A.NAME
WHERE X.COUNTER = 1
Returns:
email name id
------------------------------
jimmy#domain.com jimmy 4
brian#domain.com brian 4
kevin#domain.com kevin 3
I have a table with Student ID's and Student Names. There has been issues with assigning unique Student Id's to students and Hence I want to find the duplicates
Here is the sample Table:
Student ID Student Name
1 Jack
1 John
1 Bill
2 Amanda
2 Molly
3 Ron
4 Matt
5 James
6 Kathy
6 Will
Here I want a third column "Duplicate_Count" to display count of duplicate records.
For e.g. "Duplicate_Count" would display "3" for Student ID = 1 and so on. How can I do this?
Thanks in advance
Select StudentId, Count(*) DupCount
From Table
Group By StudentId
Having Count(*) > 1
Order By Count(*) desc,
Select
aa.StudentId, aa.StudentName, bb.DupCount
from
Table as aa
join
(
Select StudentId, Count(*) as DupCount from Table group by StudentId
) as bb
on aa.StudentId = bb.StudentId
The virtual table gives the count for each StudentId, this is joined back to the original table to add the count to each student record.
If you want to add a column to the table to hold dupcount, this query can be used in an update statement to update that column in the table
This should work:
update mytable
set duplicate_count = (select count(*) from mytable t where t.id = mytable.id)
UPDATE:
As mentioned by #HansUp, adding a new column with the duplicate count probably doesn't make sense, but that really depends on what the OP originally thought of using it for. I'm leaving the answer in case it is of help for someone else.
I have a database which tries to acheive point-in-time information by having a master table and a history table which records when fields in the other table will/did change. e.g.
Table: Employee
Id | Name | Department
-----------------------------
0 | Alice | 1
1 | Bob | 1
Table: History
ChangeDate | Field | RowId | NewValue
---------------------------------------------
05/05/2009 | Department | 0 | 2
That records that employee 0 (Alice) will move to department 2 on 05/05/2009.
I want to write a query to determine the employee's department on a particular date. So it needs to:
Find the first history record for that field and employee before given date
If none exists then default to the value currently in the master employee table.
How can I do this? My intuition is to select the first row of a result set which has all suitable history records reverse ordered by date and with the value in the master table last (so it's only the first result if there are no suitable history records), but I don't have the required SQL-fu to achieve this.
Note: I am conscious that this may not be the best way to implement this system - I am not able to change this in the short term - though if you can suggest a better way to implement this I'd be glad to hear it.
SELECT COALESCE (
(
SELECT newValue
FROM history
WHERE field = 'Department'
AND rowID = ID
AND changeDate =
(
SELECT MAX(changedate)
FROM history
WHERE field = 'Department'
AND rowID = ID
AND changeDate <= '01/01/2009'
)
), department)
FROM employee
WHERE id = #id
In both Oracle and MS SQL, you can also use this:
SELECT COALESCE(newValue, department)
FROM (
SELECT e.*, h.*,
ROW_NUMBER() OVER (PARTITION BY e.id ORDER BY changeDate) AS rn
FROM employee e
LEFT OUTER JOIN
history h
ON field = 'Department'
AND rowID = ID
AND changeDate <= '01/01/2009'
WHERE e.id = #id
)
WHERE rn = 1
Note, though, that ROWID is reserved word in Oracle, so you'll need to rename this column when porting.
This should work:
select iif(history.newvalue is null, employee.department, history.newvalue)
as Department
from employee left outer join history on history.RowId = employee.Id
and history.changedate < '2008-05-20' // (i.e. given date)
and history.changedate = (select max(changedate) from history h1
where h1.RowId = history.RowId and h1.changedate <= history.changedate)