I'm trying to get unique Value from two tables but the problem is the data in 'd.feedback' is displaying all of the data in the column feedback from daily_report table.
This is the code that I use. So what do you think I should do? Distinct fullname and feedback? or is there another alternative?
SET #row := 0;
SELECT DISTINCT CONCAT(#row := #row + 1,' ',ui.firstname) as 'Regular Users', d.feedback
FROM daily_report d
INNER JOIN userinfo ui ON d.userid = ui.id
Here is the First Table
| id | firstname |
| -- | ----------|
| 1 | Christian |
| 2 | Levi |
| 3 | Brian |
Here is the Second Table
| userid| feedback | id |
| -- | ----------|--------|
| 1 | Thanks | 1 |
| 2 | Arigato | 1 |
| 3 | Sure | 2 |
| 4 | Thank you | 2 |
| 5 | Thank you | 2 |
| 6 | Thank you | 2 |
Desired output
Regular User
feedback
1 Christian
Thanks
2 Christian
Arigato
3 Levi
Sure
4 Levi
Thank you
And Here is my problem
I''m am getting duplicate value like Number 2 and 4
I think this does what you want
SELECT CONCAT(#row := #row + 1,' ',ui.firstname) as 'Regular Users',
d.feedback
FROM (select distinct feedback, userid from daily_report) d INNER JOIN userinfo ui ON d.userid = ui.userid;```
This query allows DISTINCT to do its job.
SELECT DISTINCT ui.firstname as 'Regular Users',
d.feedback
FROM daily_report d INNER JOIN userinfo ui ON d.userid = ui.userid;
When you do DISTINCT CONCAT(#row := #row + 1,' ',ui.firstname) as 'Regular Users' you make every value of Regular Users different from the others, which defeats DISTINCT.
Related
I need to get AVG for every row in SQL for example:
this is the first table
+ ---+------+-------------+
| course_id | course_name |
+ ----------+-------------+
| 1 | a |
| 2 | b |
| 3 | c |
| 4 | g |
+ ---+------+-------------+
This is the second table
I need to get AVG for both id 1 and 2. the result for example:
+ -------------------+------+----------+
| course_feedback_id | rate |course_id |
+ -================--+------+----------+
| 1 | 4 | 1 |
| 2 | 3 | 1 |
| 3 | 2 | 2 |
+ -------------------+------+----------+
this is the final answer that i need
+ ----------------------+
| course_id | AVG(rate) |
+ -=======--+-----------+
| 1 | 3.5 |
| 2 | 2 |
+ ----------------------+
I tried this soulution but it will give me only the first row not all records.
SELECT *, AVG(`rate`) from secondTable
please help
SELECT `id`, AVG(`rate`) FROM `your_table` GROUP BY `id`
Try this:
SELECT c.course_id, AVG(fb.rate)
FROM course AS c
INNER JOIN course_feedback AS fb ON fb.course_id = c.course_id
GROUP BY c.course_id
Select course_id,t2.rate from table1 where course_id,rate in (Select course_id,avg(rate) as rate from table group by course_id t2)
When you have multiple entries/redundant entries and you want to find some aggregation per each as in this case you got id containing redundant records, In such cases always try to use group by as group by as the name says will group records of the column to which it is applied and if you apply aggregation avg in this case will be groupwise column to which it is being applied not as a whole like for id 1 we have 2 redundant entries so itll apply avg(id1_entries)..likewise as a group.
I have two tables in mysql. The first one has user data for example, the second one has attributes data.
I want to select each user from table one and get all attributes for him from table two.
e.g.
table 1:
| userid | name |
| 1 | John |
| 2 | Billie |
table 2:
| userid | attribute |
| 1 | male |
| 1 | taxi driver |
| 1 | 45 years |
| 2 | female |
| 2 | clerk |
So I want to get my mysql results like this:
| userid | name | attributes |
| 1 | John | male, taxi driver, 45 years |
| 2 | Billie | female, clerk |
I absolutely have noch idea, how to get these attributes consolidated (maybe even comma seperated). I also searched here, but found nothing similar.
Can you help please? Thanks
I think you can user GROUP_CONCAT for that perhaps.
SELECT userid, name, GROUP_CONCAT(attribute) as attributes
FROM table1
INNER JOIN table2 ON table1.userid = table2.userid
GROUP BY table2.userid
See this SQLFiddle example: http://sqlfiddle.com/#!9/fd365d4/6/0
;with SampleDataR as
(
select *, ROW_NUMBER() over (partition by title, subtitle order by value) rownum
from test12
)
select distinct title, subtitle,(
select value
+ case when s1.rownum = (select MAX(rownum) from SampleDataR where title = s1.title and subtitle = s1.subtitle)
then '' else ',' end from SampleDataR s1
where s1.title = s2.title and s1.subtitle = s2.subtitle
for xml path(''),type).value('(.)[1]','varchar(max)') csvList
from SampleDataR s2
I have an abstract problem which can be simplified as the following problem: Assume that we have two tables persons and names that look as follows:
SELECT * FROM persons;
+----+-------+--------+
| id | name | fan_of |
+----+-------+--------+
| 1 | alice | 2 |
| 2 | bob | 4 |
| 3 | carol | 1 |
| 4 | dave | 3 |
| 5 | bob | 2 |
+----+-------+--------+
and
SELECT * FROM names;
+----+-------+--------+
| id | name | active |
+----+-------+--------+
| 1 | alice | 1 |
| 2 | bob | 1 |
| 3 | carol | 0 |
| 4 | dave | 1 |
+----+-------+--------+
Every person (a row in the persons) table is a fan of itself or another person (represented by that other persons id in the fan_of column). The names table contains names that can be active or inactive.
For a given offset k, I want to SELECT the persons (rows of persons) that have the k+1-th active name as their name or that have one of these people as their fans. For example, if the offset is 1, the second active name is bob and hence I want to select all people with the name bob plus the people that have one of these bobs as their fans, which is in this example the row of persons with id=4. This means that I want to have the result:
+----+------+--------+
| id | name | fan_of |
+----+------+--------+
| 2 | bob | 4 |
| 4 | dave | 3 |
| 5 | bob | 2 |
+----+------+--------+
What I have so far is the following query:
1 SELECT * FROM persons WHERE
2 EXISTS (
3 SELECT * FROM (
4 SELECT * FROM names WHERE active=true LIMIT 1 OFFSET 1
5 ) AS selectedname WHERE (selectedname.name=persons.name)
6 )
7 OR
8 EXISTS (
9 SELECT * FROM(
10 SELECT * FROM persons WHERE EXISTS (
11 SELECT * FROM (
12 SELECT * FROM names WHERE active=true LIMIT 1 OFFSET 1
13 ) AS selectedname WHERE (selectedname.name=persons.name)
14 )
15 ) AS personswiththatname WHERE persons.id=personswiththatname.fan_of
16 );
It gives me the desired result from above but please note that it is inefficient because the lines 3-5 and 11-13 are the same.
I have the following two questions:
What can be done to avoid this inefficiency?
I actually need to distinguish between those rows that came from the
name condition (here the rows with name=bob) and those that came
from the fan_of condition (here the row with name=dave). This
could be done in the application code but then I would need another
database query before to find out the k+1-th active name and this might
be slow (please correct me if this is the better solution). I would
rather prefer an additional column z that helps me to distinguish
like
+----+------+--------+---+
| id | name | fan_of | z |
+----+------+--------+---+
| 2 | bob | 4 | 1 |
| 4 | dave | 3 | 0 |
| 5 | bob | 2 | 1 |
+----+------+--------+---+
How can such an output be achieved?
It looks like I can get the minimum you want to achieve using parameters (should this be an option).
It's not pretty, but I can't see a simple way of achieving what you're asking for, so this is what I have so far....(set #offset to suit 'k')
SET #offset = 1;
SET #name = (SELECT name FROM (select name, #rank := #rank +1 as Rank from names n, (SELECT #rank := 0) r where active !=0) as activeRanked where activeRanked.rank = (1 + #offset));
select
a.*
From persons a
where (a.name = #name) OR (a.id IN (SELECT fan_of from persons where name = #name));
If you still don't have an answer by the time I've had food, I'll look at part 2.
(hopefully I've read your brief correctly)
P.S. I've kept the #name SQL in a single line as it seems to read better in this context.
Edit: Here's a pretty messy but functional indicator of source, using your example. Z = 1 is where the row is from the name, '0' is from fan_of
SET #offset = 1;
SET #name = (SELECT name FROM (select name, #rank := #rank +1 as Rank from names n, (SELECT #rank := 0) r where active !=0) as activeRanked where activeRanked.rank = (1 + #offset));
select
a.*,'1' as z
From persons a
where (a.name = #name)
union
select
a.*,'0' as z
From persons a
where (a.id IN (SELECT fan_of from persons where name = #name));
Distinct ID Query:
SET #offset = 1;
SET #name = (SELECT name FROM (select name, #rank := #rank +1 as Rank from names n, (SELECT #rank := 0) r where active !=0) as activeRanked where activeRanked.rank = (1 + #offset));
SELECT id, name, fan_of, z FROM
(select
distinct a.id,
a.name,
a.fan_of,
1 as z
From persons a
where (a.name = #name)
union
select
distinct a.id,
a.name,
a.fan_of,
0 as z
From persons a
where (a.id IN (SELECT fan_of from persons where name = #name))
ORDER BY z desc) qry
GROUP BY id;
This produces:
+----+------+--------+---+
| id | name | fan_of | z |
+----+------+--------+---+
| 2 | bob | 4 | 1 |
| 5 | bob | 2 | 1 |
| 4 | dave | 3 | 0 |
+----+------+--------+---+
Tables
__________________ ________________________________
|______name________| |____________scores______________|
|___id___|__name___| |_id_|_user-id_|_name-id_|_score_|
| 1 | bob | | 1 | 3 | 1 | 5 |
| 2 | susan | | 2 | 1 | 3 | 4 |
| 3 | geoff | | 3 | 3 | 2 | 3 |
| 4 | larry | | 4 | 2 | 4 | 5 |
| 5 | peter | | 5 | 1 | 1 | 0 |
-------------------- ----------------------------------
Im looking to write a query that returns a RANDOM name from the 'name' table, that the user hasnt scored so far.
So given user '1' for example, it could return 'susan, larry or peter' as user '1' hasnt given them a score yet.
SELECT *
FROM names
LEFT JOIN
votes
ON names.id = votes.name_id
WHERE votes.user_id = 1
AND (votes.score IS NULL);
So far I have this, but it doesnt seem to be working as I would like
(atm it doesnt return a random, but all, but this is wrong)
Any help would be appreciated.
If you are filtering on some field of outer joined table type of join is automatically changed to inner. In your case it's condition
votes.user_id = 1
So you need to move that condition from WHERE to ON
SELECT *
FROM names
LEFT JOIN
votes
ON names.id = votes.name_id and votes.user_id = 1
WHERE (votes.score IS NULL);
Consider moving the condition from WHERE to JOIN ON clause since you are performing an OUTER JOIN else the effect would be same as INNER JOIN
LEFT JOIN votes
ON names.id = votes.name_id
AND votes.user_id = 1
WHERE votes.score IS NULL
ORDER BY RAND();
You could apply :
SELECT name FROM name join scores on name.id=scores.user_id WHERE scores.score=0
You can perform this as a sub-query
SELECT *
FROM names
WHERE id NOT IN (SELECT name_id FROM votes WHERE user_id=1)
ORDER BY RAND()
LIMIT 1
I have two tables messages and users I want to find out which users received the messages however the query is only returning one message.
My Schemas are as follow
Messages
msg_id | msg_content | recipients |
-----------------------------------
1 | Hello world | 1,2,3,4,5
2 | Test | 1,3,5
3 | Welcome | 1,2,4
Users
uid | fname | lname |
---------------------------
1 | John |Doe |
2 | Jane |Doe |
3 | Mark |Someone |
4 | Mary |lady |
5 | Anthony |Doe |
So I would love to see my results simply as
msg_id | msg_content | recipients |
-----------------------------------
1 | Hello world | John,Jane,Mark,Mary,Anthony
2 | Test | John,Mark,Anthony
3 | Welcome | John,Jane,Mary
So I am doing my query as so
SELECT msg_id,msg_content,fname AS recepients FROM messages a
LEFT JOIN users ON uid IN(a.recipients)
When I run that query I only get one recipient. Please advice. Thanks.
I think you have to use a alternative way for create tables
Messages
msg_id | msg_content |
----------------------
1 | Hello world |
2 | Test |
3 | Welcome |
Users
uid | fname | lname |
---------------------------
1 | John |Doe |
2 | Jane |Doe |
3 | Mark |Someone |
4 | Mary |lady |
5 | Anthony |Doe |
users_has_messages
uhm_id | uid | msg_id |
---------------------------
1 | 1 | 1 |
2 | 2 | 1 |
3 | 3 | 1 |
4 | 2 | 2 |
5 | 1 | 3 |
Then you can use your code
Okay, so this schema isn't the best (using comma separated lists of IDs is not a great idea, and the performance of any joins will get pretty bad pretty quick). Best bet is to have a third table mapping uid's to msg_id's as mentioned by #Thilina.
That said, this query will do probably what you're after:
SELECT msg_id,msg_content,GROUP_CONCAT(fname) AS recepients FROM messages a
LEFT JOIN users ON FIND_IN_SET(uid, a.recipients)
GROUP BY msg_id
I tried this in Oracle 12c and it is working fine.
So basically what I did is
- Separate the userid from recipient field and used this a columns.
- Join with USERS table to get user fnames
- Used LISTAGG function to aggregate it back.
For MySql we need to find the corresponding functions to Separate the IDs between commas, Convert it to rows and Aggregate. But the inherent logic would be same.
with users (user_id,fname) as (
select 1 ,'John' from dual union
select 2 ,'Jane' from dual union
select 3 ,'Mark' from dual union
select 4 ,'Mary' from dual union
select 5 ,'Anthony' from dual
),
messages(msg_id, msg_content,recipients) as(
select 1,'Hello world','1,2,3,4,5' from dual union
select 2 , 'Test' ,'1,3,5' from dual union
select 3,' Welcome','1,2,4' from dual
),
flat as(
select msg_id,msg_content,
REGEXP_SUBSTR (recipients, '[^,]+', 1, COLUMN_VALUE) as user_id
from messages,
TABLE(
CAST(
MULTISET(
SELECT LEVEL
FROM DUAL
CONNECT BY LEVEL <= REGEXP_COUNT(recipients ,',' ) + 1
) AS SYS.ODCINUMBERLIST
)
)
),
unames as
( select f.msg_id,f.msg_content,u.fname from flat f inner join users u
on f.user_id = u.user_id
order by f.msg_id
)
SELECT msg_id,msg_content,LISTAGG(fname, ',') WITHIN GROUP (ORDER BY fname) as recipients
from unames
group by msg_id,msg_content