I have two tables, and am doing an ordered select on each of them. I wold like to see the results of both orders in one result.
Example (simplified):
"SELECT * FROM table1 ORDER BY visits;"
name|# of visits
----+-----------
AA | 5
BB | 9
CC | 12
.
.
.
"SELECT * FROM table2 ORDER BY spent;"
name|$ spent
----+-------
AA | 20
CC | 30
BB | 50
.
.
.
I want to display the results as two columns so I can visually get a feeling if the most frequent visitors are also the best buyers. (I know this example is bad DB design and not a real scenario. It is an example)
I want to get this:
name by visits|name by spent
--------------+-------------
AA | AA
BB | CC
CC | BB
I am using SQLite.
Select A.Name as NameByVisits, B.Name as NameBySpent
From (Select C.*, RowId as RowNumber From (Select Name From Table1 Order by visits) C) A
Inner Join
(Select D.*, RowId as RowNumber From (Select Name From Table2 Order by spent) D) B
On A.RowNumber = B.RowNumber
Try this
select
ISNULL(ts.rn,tv.rn),
spent.name,
visits.name
from
(select *, (select count(*) rn from spent s where s.value>=spent.value ) rn from spent) ts
full outer join
(select *, (select count(*) rn from visits v where v.visits>=visits.visits ) rn from visits) tv
on ts.rn = tv.rn
order by ISNULL(ts.rn,tv.rn)
It creates a rank for each entry in the source table, and joins the two on their rank. If there are duplicate ranks they will return duplicates in the results.
I know it is not a direct answer, but I was searching for it so in case someone needs it: this is a simpler solution for when the results are only one per column:
select
(select roleid from role where rolename='app.roles/anon') roleid, -- the name of the subselect will be the name of the column
(select userid from users where username='pepe') userid; -- same here
Result:
roleid | userid
--------------------------------------+--------------------------------------
31aa33c4-4e66-4da3-8525-42689e46e635 | 12ad8c95-fbef-4287-9834-7458a4b250ee
For RDBMS that support common table expressions and window functions (e.g., SQL Server, Oracle, PostreSQL), I would use:
WITH most_visited AS
(
SELECT ROW_NUMBER() OVER (ORDER BY num_visits) AS num, name, num_visits
FROM visits
),
most_spent AS
(
SELECT ROW_NUMBER() OVER (ORDER BY amt_spent) AS num, name, amt_spent
FROM spent
)
SELECT mv.name, ms.name
FROM most_visited mv INNER JOIN most_spent ms
ON mv.num = ms.num
ORDER BY mv.num
Just join table1 and table2 with name as key like bellow:
select a.name,
b.name,
a.NumOfVisitField,
b.TotalSpentField
from table1 a
left join table2 b on a.name = b.name
Related
Query
select
a.id,
a.ba,
b.status,
b.custid
from balist as a
inner join customer as b
on a.ba = b.ba
I have a table "balist" that has a list of (ba) and i inner join table "customer" on (ba) and right now by output is like the following
id
ba
status
custid
1
ba-1234455
A
123-321-123-321a
2
ba-1234455
I
123-321-123-321a
3
ba-1234457
A
123-321-123-321b
4
ba-1234458
A
123-321-123-321c
5
ba-1234459
I
123-321-123-321d
and I want to return all A and I status but remove the row that has status I that also have a A status. Like the following.
I have a table customer like the following
id
ba
status
custid
1
ba-1234455
A
123-321-123-321a
3
ba-1234457
A
123-321-123-321b
4
ba-1234458
A
123-321-123-321c
5
ba-1234459
I
123-321-123-321d
You could use a row_number() to filter your resulting rows eg
SELECT
id,ba,status,custid
FROM (
SELECT
a.id,
a.ba,
b.status,
b.custid,
ROW_NUMBER() OVER (
PARTITION BY a.ba
ORDER BY b.status ASC
) as rn
FROM
balist as a
INNER JOIN
customer as b ON a.ba = b.ba
)
WHERE rn=1
Let me know if this works for you.
I'm having the following request to get all artworks inner join with their user info:
SELECT a.*, row_to_json(u.*) as users
FROM artworks a INNER JOIN users u USING(address)
WHERE (a.flag != "ILLEGAL" OR a.flag IS NULL)
ORDER BY a.date DESC
LIMIT 100
How could i have the same query but including no more than 3 entries per user?
Each user have a unique id called "address"
I think DISTINCT ON only work for 1 per user, maybe ROW_NUMBER?
Thank you in advance, i'm pretty new to DB queries.
You need an extra column in which you specify the nth time that the user is in the table. This will look something like this:
USER | N
user1 | 1
user1 | 2
user1 | 3
user2 | 1
user2 | 2
Getting the extra column in a new table can be done by using the following code
--Create new Table as T
WITH T AS (
SELECT TOP 100
a.*,
row_to_json(u.*) as users,
ROW_NUMBER() OVER(PARTITION BY u.user ORDER BY a.date DESC) AS N
FROM artworks a INNER JOIN users u USING(address)
WHERE (a.flag != "ILLEGAL" OR a.flag IS NULL) )
--Select columns from your new table
SELECT columns from T
WHERE (T.N =1 OR T.N =2 OR T.N =3)
Just an addition to your original query will do. Count the resulting records for each user and then filter by the counter value.
I am using users.address as the user id.
SELECT * from
(
SELECT a.*, row_to_json(u.*) as userinfo,
row_number() over (partition by u.address order by a.date desc) as ucount
FROM artworks a INNER JOIN users u ON a.address = u.address
WHERE a.flag != "ILLEGAL" OR a.flag IS NULL
) t
WHERE ucount <= 3
ORDER BY date DESC
LIMIT 100;
A remark - you have users as a column alias and as a table name which may cause confusion. I have changed the alias to userinfo.
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;
This is my query,
SELECT top 100
UPPER(COALESCE(A.DESCR,C.FULL_NAME_ND)) AS DESCR,
COALESCE(A.STATE, (SELECT TOP 1 STATENAME
FROM M_STATEMASTER
WHERE COUNTRYCODE = B.CODE)) AS STATENAME,
COALESCE(A.STATECD, (SELECT TOP 1 CODE
FROM M_STATEMASTER
WHERE COUNTRYCODE = B.CODE)) AS STATECD,
COALESCE(A.COUNTRYCD, B.CODE) AS COUNTRYCODE
FROM
M_CITY A
JOIN
M_COUNTRYMASTER B ON A.COUNTRYCD = B.CODE
JOIN
[GEODATASOURCE-CITIES-FREE] C ON B.ALPHA2CODE = C.CC_FIPS
WHERE
EXISTS (SELECT 1
FROM [GEODATASOURCE-CITIES-FREE] Z
WHERE B.ALPHA2CODE=Z.CC_FIPS)
ORDER BY
A.CODE
Perfectly working fine, but when I'm trying to get the Row_number() over(order by a.code) I'm getting the duplicate column multiple time.
e.g
SELECT top 100
UPPER(COALESCE(A.DESCR,C.FULL_NAME_ND)) AS DESCR,
COALESCE(A.STATE, (SELECT TOP 1 STATENAME
FROM M_STATEMASTER
WHERE COUNTRYCODE = B.CODE)) AS STATENAME,
COALESCE(A.STATECD, (SELECT TOP 1 CODE
FROM M_STATEMASTER
WHERE COUNTRYCODE = B.CODE)) AS STATECD,
COALESCE(A.COUNTRYCD, B.CODE) AS COUNTRYCODE
ROW_NUMBER() OVER(ORDER BY A.CODE) AS RN -- i made a change here
FROM
M_CITY A
JOIN
M_COUNTRYMASTER B ON A.COUNTRYCD = B.CODE
JOIN
[GEODATASOURCE-CITIES-FREE] C ON B.ALPHA2CODE = C.CC_FIPS
WHERE
EXISTS (SELECT 1
FROM [GEODATASOURCE-CITIES-FREE] Z
WHERE B.ALPHA2CODE=Z.CC_FIPS)
ORDER BY
A.CODE
WHERE
EXISTS (SELECT 1
FROM [GEODATASOURCE-CITIES-FREE] Z
WHERE B.ALPHA2CODE = Z.CC_FIPS)
Another try, when I'm using ROW_NUMBER() OVER(ORDER BY newid()) AS RN it's taking logn time to execute.
Remember: CODE is the Pk of table M_CITY and there is no key in [GEODATASOURCE-CITIES-FREE] table.
Another thing: About JOIN(inner join), Join returns the matched Rows, right???
e.g:
table 1 with 20 rows,
table2 with 30 rows ,
table 3 with 30 rows
If I joined these 3 table on a certain key then the possibility of getting maximum rows is 20, am I right?
Your first query doesn't work fine. It just appears to. The reason is that you are using TOP without an ORDER BY, so an arbitrary set of 100 rows is returned.
When you add ROW_NUMBER(), the query plan changes . . . and the ordering of the result set changes as well. I would suggest that you fix the original query to use a stable sort.
Hi I'm new to SQL and I'm trying to figure out how I'm going to get the top 5 "bands" with most friends (userId) and this is what i have; a usertbl with userId as PK then a bandsTbl with bandId as PK then I have a table bandfriends with FK userId and bandId.
bandfriends
userid | bandId
---------------
1 | 1
1 | 2
1 | 3
Thanks!
SELECT TOP 5 bandId, fanCount
FROM
(SELECT bandId, COUNT(*) as fanCount
FROM bandfriends
GROUP BY bandId
ORDER BY COUNT(*) DESC)
You can also optionally specify WITH TIES in the select statement. See this and this.
select top 5 b.b_name, count(friends) as numOfFriends
from bands b inner join link l on b.b_id = l.bands inner join
friends f on f.f_id = l.friends
group by b.b_name
order by numOfFriends desc
If you have friends table, bands table and a link table, works for me :)
Read up on COUNT and GROUP BY at mysql.org
You'll want something like this (I haven't tested it):
SELECT bandId, COUNT(*) as fans FROM bandfriends
ORDER BY fans DESC
GROUP BY bandId
LIMIT 5;