I have tables:
Person
-------------
ID | name
Notes
---------------------------
targetID | Content | Date
CallHistory
--------------------------
CallerID | CalleeID | Date
Now say I have a Person and a Spouse (which is on the same Person table).
They have corresponding notes and callhistory.
What I want is to Select the most recent date from either the spouse or person's most recent date (call or note)
Ive tried:
SELECT top 1 Date, ID from (select TargetID as ID, Date from notes
union
SELECT CalleeID as ID, Date from Callhistory)
WHERE ID in (person.ID, spouse.ID)
but without luck.
EDIT: This select is inside a select statement:
select p.*, SELECT top 1 Date, ID from (select TargetID as ID, Date from notes
union
SELECT CalleeID as ID, Date from Callhistory)
WHERE ID in (person.ID, spouse.ID) as RecentContactDate
From Person person
LEFT JOIN PersonRelationship pr on person.ID = pr.ID AND pr.Type = 3 -- spouse
LEFT JOIN Person spouse on pr.RelatedID = spouse.ID
......
Im getting Ambigous column name Date error.
any ideas?
#Sven's answer on this post has helped me solve my problem: SQL MAX of multiple columns?
What I've done is join the two tables from the two persons into a single row (need to get the MAX dates for each person's tables - CallHistory and Notes). Then get the MAX out of that four columns. So here's the fix:
select p.*,
(SELECT Max(v)
FROM (VALUES (pNote.Date), (pCh.Date), (sNote.Date),(sCh.Date)) AS value(v)) as [MaxDate]
WHERE ID in (person.ID, spouse.ID) as RecentContactDate
From Person person
LEFT JOIN PersonRelationship pr on person.ID = pr.ID AND pr.Type = 3 -- spouse
LEFT JOIN Person spouse on pr.RelatedID = spouse.ID
LEFT JOIN (SELECT ID, MAX(Date) from Notes) pNote on pNote.targetID = person.ID
LEFT JOIN (SELECT ID, MAX(Date) from CallHistory) pCh on person.ID = ch.CalleeID
LEFT JOIN (SELECT ID, MAX(Date) from Notes) sNote on spouse.ID = pNote.targetID
LEFT JOIN (SELECT ID, MAX(Date) from CallHistory) sCh on spouse.ID = ch.CalleeID
I hope this will help anyone in the future.
Related
I want to create a random selected cross-joined table which auto increments its own id and joins on it.
Let's say my tables looking like this.
Person
Firstname, Lastname
Hans | Müller
Joachim | Bugert
Address
City, Street, StreetNumber
Hamburg | Wandsbeckerstr. | 2
Berlin | Konradstraße | 13
Now I want to join the tables with a auto generated ID and they should be random selected.
The final table should look like this
ID,Firstname,Lastname, City, Street, StreetNumber
1 |Hans|Bugert|Berlin|Wandsbeckerstr|2
2|Joachim|Müller|Hamburg|Konradstraße | 13
What I already tried or used:
Here I auto-generate the ID where I want to join the tables on
select GENERATED_PERIOD_START as ID FROM SERIES_GENERATE_INTEGER(1,1,10)
The problem is cross join and inner join isn't working for me because it always joins everything with everything or its not joining on the same ID.
SELECT Person."Firstname", Person."Lastname", Address."City",Address."Street", Address."StreetNumber"
FROM
( select GENERATED_PERIOD_START as ID FROM SERIES_GENERATE_INTEGER(1,1,10)
) autoGenID
inner JOIN
(select "Firstname" ,"Lastname" FROM Person ORDER BY RAND()) Person
inner JOIN
(select "City", "Street", "StreetNumber", FROM Address ORDER BY RAND()) Address
JOIN ON autoGenID."ID"=?????
Here is my problem I can't just select random data and select that on my auto generated ID.
Thanks for your help or ideas how to solve this!
I think you want:
SELECT p."Firstname", p."Lastname", a."City", a."Street", a."StreetNumber"
FROM (SELECT p.*,
ROW_NUMBER() OVER (ORDER BY RAND()) as seqnum
FROM Person p
) p JOIN
(SELECT a.*,
ROW_NUMBER() OVER (ORDER BY RAND()) as seqnum
FROM Address a
) a
ON p.seqnum = a.seqnum;
I have 3 tables:
Person (with a column PersonKey)
Telephone (with columns Tel_NumberKey, Tel_Number, Tel_NumberType e.g. 1=home, 2=mobile)
xref_Person+Telephone (columns PersonKey, Tel_NumberKey, CreatedDate, ModifiedDate)
I'm looking to get the most recent (e.g. the highest Tel_NumberKey) from the xref_Person+Telephone for each Person and use that Tel_NumberKey to get the actual Tel_Number from the Telephone table.
The problem I am having is that I keep getting duplicates for the same Tel_NumberKey. I also need to be sure I get both the home and mobile from the Telephone table, which I've been looking to do via 2 individual joins for each Tel_NumberType - again getting duplicates.
Been trying the following but to no avail:
-- For HOME
SELECT
p.PersonKey, pn.Phone_Number, pn.Tel_NumberKey
FROM
Persons AS p
INNER JOIN
xref_Person+Telephone AS x ON p.PersonKey = x.PersonKey
INNER JOIN
Telephone AS pn ON x.Tel_NumberKey = pn.Tel_NumberKey
WHERE
pn.Tel_NumberType = 1 -- e.g. Home phone number
AND pn.Tel_NumberKey = (SELECT MAX(pn1.Tel_NumberKey) AS Tel_NumberKey
FROM Person AS p1
INNER JOIN xref_Person+Telephone AS x1 ON p1.PersonKey = x1.PersonKey
INNER JOIN Telephone AS pn1 ON x1.Tel_NumberKey = pn1.Tel_NumberKey
WHERE pn1.Tel_NumberType = 1
AND p1.PersonKey = p.PersonKey
AND pn1.Tel_Number = pn.Tel_Number)
ORDER BY
p.PersonKey
And have been looking over the following links but again keep getting duplicates.
SQL select max(date) and corresponding value
How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
SQL Server: SELECT only the rows with MAX(DATE)
Am sure this must be possible but been at this a couple of days and can't believe its that difficult to get the most recent / highest value when referencing 3 tables. Any help greatly appreciated.
select *
from
( SELECT p.PersonKey, pn.Phone_Number, pn.Tel_NumberKey
, row_number() over (partition by p.PersonKey, pn.Phone_Number order by pn.Tel_NumberKey desc) rn
FROM
Persons AS p
INNER JOIN
xref_Person+Telephone AS x ON p.PersonKey = x.PersonKey
INNER JOIN
Telephone AS pn ON x.Tel_NumberKey = pn.Tel_NumberKey
WHERE
pn.Tel_NumberType = 1
) tt
where tt.rn = 1
ORDER BY
tt.PersonKey
you have to use max() function and then you have to order by rownum in descending order like.
select f.empno
from(select max(empno) empno from emp e
group by rownum)f
order by rownum desc
It will give you all employees having highest employee number to lowest employee number. Now implement it with your case then let me know.
Imagine you have two tables, with a one to many relationship.
For this example, I will suggest that there are two tables: Person, and Homes.
The person table holds a persons name, and gives them an ID. The homes table, holds the association of homes to a person. PID joins to "Person.ID"
And, in this tiny DB, a person can have no homes, or many homes.
I hope I drew that right.
How do I write a select, that returns everyone with every specified house type?
Let's say these are valid "Types" in the homes table:
Cottage, Main, Mansion, Spaceport.
I want to return everyone, in the Person table, who has a spaceport and a Cottage.
The best I could come up with was this:
SELECT DISTINCT( p.name ) AS name
FROM person p
INNER JOIN homes h ON h.pid = p.id
WHERE 'spaceport' in (
SELECT DISTINCT( type ) AS type
FROM homes
WHERE pid = p.id
)
AND 'cottage' in (
SELECT DISTINCT( type ) AS type
FROM homes
WHERE pid = p.id
)
When I wrote that, it works, but I'm pretty sure there has to be a better way.
The HAVING clause here will guarantee that the persons returned have both types, not just one or the other.
SELECT p.name
FROM person p
INNER JOIN homes h
ON p.id = h.pid
AND h.type IN ('spaceport', 'cottage')
GROUP BY p.name
HAVING COUNT(DISTINCT h.type) = 2
select * from homes;
home_id person_id type
--
1 1 cottage
2 1 mansion
3 2 cottage
4 3 mansion
5 4 cottage
6 4 cottage
To find the id numbers of every person who has both a cottage and a mansion, group by the id number, restrict the output to cottages and mansions, and count the distinct types.
select person_id
from homes
where type in ('cottage','mansion')
group by person_id
having count(distinct type) = 2;
person_id
--
1
You can use this query in a join to get all the columns from the person table.
select person.*
from person
inner join (select person_id
from homes
where type in ('cottage','mansion')
group by person_id
having count(distinct type) = 2) T
on person.person_id = T.person_id;
Thanks to Joe for pointing out an error in my count().
Not sure about the performance on this one, but here goes:
SELECT PID FROM (
SELECT PID, COUNT(PID) cnt FROM (
SELECT DISTINCT PID, Type FROM Homes
WHERE Type IN ('Type1', 'Type2', 'Type3')
) a
GROUP BY PID
) b
WHERE b.cnt = 3
You'd have to dynamically generate your IN clause as well as the WHERE b.CNT clause.
Let's say I have a Person table and a Purchases table with a 1 to many relationship. I want to run a single query that returns this person and just their latest purchase. This seems easy but I just can't seem to get it.
select p.*, pp.*
from Person p
left outer join (
select PersonID, max(PurchaseDate) as MaxPurchaseDate
from Purchase
group by PersonID
) ppm
left outer join Purchase pp on ppm.PersonID = pp.PersonID
and ppm.MaxPurchaseDate = pp.PurchaseDate
where p.PersonID = 42
This query will also show the latest purchase for all users if you remove the WHERE clause.
Assuming you have something like a PurchaseDate column and want a particular person (SQL Server):
SELECT TOP 1 P.Name, P.PersonID, C.PurchaseDescription FROM Persons AS P
INNER JOIN Purchases AS C ON C.PersonID = P.PersonID
WHERE P.PersonID = #PersonID
ORDER BY C.PurchaseDate DESC
Many Databases preform the "Limit or Top" command in different ways. Here is a reference http://troels.arvin.dk/db/rdbms/#select-limit and below are a few samples
If using SQL Server
SELECT TOP 1
*
FROM Person p
INNER JOIN Purchases pc on pc.PersonID = P.PersonID
Order BY pc.PurchaseDate DESC
Should work on MySQL
SELECT
*
FROM Person p
INNER JOIN Purchases pc on pc.PersonID = P.PersonID
Order BY pc.PurchaseDate DESC
LIMIT 1
Strictly off the top of my head!...If it's only one record then...
SELECT TOP 1 *
FROM Person p
INNER JOIN Purchases pu
ON p.ID = p.PersonId
ORDER BY pu.OrderDate
WHERE p.ID = *thePersonYouWant*
otherwise...
SELECT TOP 1 *
FROM Person p
INNER JOIN
(
SELECT TOP 1 pu.ID
FROM Purchases pu
ON pu.PersonID = p.Id
ORDER BY pu.OrderDate
) sq
I think! I haven't got access to a SQL box right now to test it on.
Without knowing your structure at all, or your dbms, you would order the results descending by the purchase date/time, and return only the first joined record.
Try TOP 1 With an order by desc on date. Ex:
CREATE TABLE #One
(
id int
)
CREATE TABLE #Many
(
id int,
[date] date,
value int
)
INSERT INTO #One (id)
SELECT 1 UNION ALL
SELECT 2 UNION ALL
SELECT 3
INSERT INTO #Many (id, [date], value)
SELECT 1, GETDATE(), 1 UNION ALL
SELECT 1, DATEADD(DD, 1 ,GETDATE()), 3 UNION ALL
SELECT 1, DATEADD(DD, -1 ,GETDATE()), 0
SELECT TOP 1 *
FROM #One O
JOIN #Many M ON O.id = M.id
ORDER BY [date] DESC
If you want to select the latest purchase for each person, that would be:
SELECT PE.ID, PE.Name, MAx(PU.pucrhaseDate) FROM Persons AS PE JOIN PURCHASE as PU ON PE.ID = PU.Person_ID
If you want to have all persons also those who have no purchases, you need to use LEFT JOIN.
I think you need one more table called Items for example.
The PERSONS table would uniquely define each person and all their attributes, while the ITEMS table would uniquely define each items and their attributes.
Assume the following:
Persons |Purchases |Items
PerID PerName |PurID PurDt PerID ItemID |ItemID ItemDesc ICost
101 Joe Smith |201 101107 101 301 |301 Laptop 500
|202 101107 101 302 |302 Desktop 699
102 Jane Doe |203 101108 102 303 |303 iPod 199
103 Jason Tut |204 101109 101 304 |304 iPad 499
|205 101109 101 305 |305 Printer 99
One Person Parent may tie to none, one or many Purchase Child.
One Item Parent may tie to none, one or many Purchase Child.
One or more Purchases Children will tie to one Person Parent, and one Item Parent.
select per.PerName as Name
, pur.PurDt as Date
, itm.ItemDesc as Item
, itm.ICost as Cost
from Persons per
, Purchases pur
, Items itm
where pur.PerID = per.PerID -- For that Person
and pur.ItemID = itm.ItemID -- and that Item
and pur.PurDt = -- and the purchase date is
( Select max(lst.PurDt) -- the last date
from Purchases lst -- purchases
where lst.PerID = per.PerID ) -- for that person
This should return:
Name Date Item Cost
Joe Smith 101109 Ipad 499
Joe Smith 101109 Printer 99
Jane Doe 101108 iPod 199
If I have three columns in my MySQL table people, say id, name, created where name is a string and created is a timestamp.. what's the appropriate query for a scenario where I have 10 rows and each row has a record with a name. The names could have a unique id, but a similar name none the less. So you can have three Bob's, two Mary's, one Jack and 4 Phil's.
There is also a hobbies table with the columns id, hobby, person_id.
Basically I want a query that will do the following:
Return all of the people with zero hobbies, but only check by the latest distinct person created, if that makes sense. Meaning if there is a Bob person that was created yesterday, and one created today.. I only want to know if the Bob created today has zero hobbies. The one from yesterday is no longer relevant.
select pp.id
from people pp, (select name, max(created) from people group by name) p
where pp.name = p.name
and pp.created = p.created
and id not in ( select person_id from hobbies )
SELECT latest_person.* FROM (
SELECT p1.* FROM people p1
WHERE NOT EXISTS (
SELECT * FROM people p2
WHERE p1.name = p2.name AND p1.created < p2.created
)
) AS latest_person
LEFT OUTER JOIN hobbies h ON h.person_id = latest_person.id
WHERE h.id IS NULL;
Try This:
Select *
From people p
Where timeStamp =
(Select Max(timestamp)
From people
Where name = p.Name
And not exists
(Select * From hobbies
Where person_id = p.id))