Im trying to merge two SELECT results into one view.
The first query returns the id's of all registered users.
The second query goes through an entire table and counts how many victories a player has and returns the id of the player and number of wins.
What I'm trying to do now is to merge these two results, so that if the user has wins it states how many but if he doesn't then it says 0.
I tried doing it like this:
SELECT profile.user_id
FROM profile
FULL JOIN ( SELECT player_game_data.user_id,
count(player_game_data.user_id) AS wins
FROM player_game_data
WHERE player_game_data.is_winner = 1
GROUP BY player_game_data.user_id) t2 ON profile.user_id::text = t2.user_id::text;
But in the end it only returns id's of the players and there isn't a count column:
What am I doing wrong?
Is this what you want?
select p.*,
(select count(*)
from player_game_data pg
where pg.user_id = p.user_id and pg.is_winner = 1
) as num_wins
from profile p;
Or, if all users have played at least one game, you can use conditional aggregation:
select pg.user_id,
count(*) filter (where pg.is_winner = 1)
from player_game_data pg
group by pg.user_id;
Or, if is_winner only takes on the values of 0 and 1:
select pg.user_id, sum(ps.is_winner)
from player_game_data pg
group by pg.user_id;
Thanks for the help Gordon. I've got it to work now.
The final query looks like this :
SELECT p.user_id,
( SELECT count(*) AS count
FROM player_game_data pg
WHERE pg.user_id::text = p.user_id::text AND pg.is_winner = 1) AS wins,
( SELECT count(*) AS count
FROM player_game_data pg
WHERE pg.user_id::text = p.user_id::text AND pg.is_winner = 0) AS losses,
( SELECT count(*) AS count
FROM player_game_data pg
WHERE pg.user_id::text = p.user_id::text) AS games_played
FROM profile p;
And when I run it I get the result that i wanted:
Related
Im doing following query to select out a serialnumber from table Alerts, and then count how many alerts there is for that serialnumber together with the count on how many measurements there also is for that serialnumber. Measurements is stored in another table. (first 2 queries is jsut there to show you the result for better understanding)
SELECT InstrumentSerialNumber FROM [dbo].[CloudMeasurements]
SELECT InstrumentSerialNumber FROM [dbo].[CloudAlerts]
SELECT
DISTINCT InstrumentSerialNumber,
(SELECT COUNT(*) FROM [CloudAlerts] WHERE [CloudAlerts].InstrumentSerialNumber = InstrumentSerialNumber) AS Alerts,
(SELECT COUNT(*) FROM [CloudMeasurements] WHERE [CloudMeasurements].InstrumentSerialNumber = InstrumentSerialNumber) AS Measurements
FROM [CloudAlerts]
Result
See picture for result of the query.
I assume it respond with Count(*) summarized which makes it wrong from my perspective. How do I write this?
Greetings
Try joining the results of their groups:
SELECT
A.InstrumentSerialNumber,
A.TotalAlerts,
ISNULL(M.TotalMeasurements, 0) TotalMeasurements
FROM
(SELECT InstrumentSerialNumber, COUNT(*) TotalAlerts FROM [CloudAlerts] GROUP BY InstrumentSerialNumber) AS A
LEFT JOIN (SELECT InstrumentSerialNumber, COUNT(*) TotalMeasurements FROM [CloudMeasurements] GROUP BY InstrumentSerialNumber)
AS M ON M.InstrumentSerialNumber = A.InstrumentSerialNumber
I am trying to produce the results of a pool match. I am counting the number of frames that a player has won in a match however am having difficulty producing results for those that have not won a frame.
I have read that when using a count and a group by records that return 0 are removed but am unsure on any other methods that I could use.
Please can you advise how I can improve my query below, Thank you :)
select
t1.Match_ID,
t1.Home_Player_ID,
Frames_Won,
coalesce(Frames_Lost,0) as Frames_Lost
from
(
select
Match_ID,
Home_Player_ID,
count(*) as Frames_Won
from
Match
where
Home_Player_Win = 1
and
Match_ID = '56D4FF05-5F33-43FC-A566-2251E790C57F'
group by
Match_ID,
Home_Player_ID
) t1
left join
(
select
Match_ID,
Home_Player_ID,
count(*) as Frames_Lost
from
Match
where
Home_Player_Win = 0
and
Match_ID = '56D4FF05-5F33-43FC-A566-2251E790C57F'
group by
Match_ID,
Home_Player_ID
) t2
on t1.Home_Player_ID = t2.Home_Player_ID
I think you're missing records where users have not won any games because of the first subquery limits where home_player_win = 1.
Is there any reason why this query won't work?
SELECT
Match_ID,
Home_Player_ID,
SUM(home_player_win)
FROM match
WHERE Match_ID = '56D4FF05-5F33-43FC-A566-2251E790C57F'
GROUP BY Match_ID, Home_Player_ID;
I have a postgresql query like this:
with r as (
select
1 as reason_type_id,
rarreason as reason_id,
count(*) over() count_all
from
workorderlines
where
rarreason != 0
and finalinsdate >= '2012-12-01'
)
select
r.reason_id,
rt.desc,
count(r.reason_id) as num,
round((count(r.reason_id)::float / (select count(*) as total from r) * 100.0)::numeric, 2) as pct
from r
left outer join
rtreasons as rt
on
r.reason_id = rt.rtreason
and r.reason_type_id = rt.rtreasontype
group by
r.reason_id,
rt.desc
order by r.reason_id asc
This returns a table of results with 4 columns: the reason id, the description associated with that reason id, the number of entries having that reason id, and the percent of the total that number represents.
This table looks like this:
What I would like to do is only display the top 10 results based off the total number of entries having a reason id. However, whatever is leftover, I would like to compile into another row with a description called "Other". How would I do this?
with r2 as (
...everything before the select list...
dense_rank() over(order by pct) cause_rank
...the rest of your query...
)
select * from r2 where cause_rank < 11
union
select
NULL as reason_id,
'Other' as desc,
sum(r2.num) over() as num,
sum(r2.pct) over() as pct,
11 as cause_rank
from r2
where cause_rank >= 11
As said above Limit and for the skipping and getting the rest use offset... Try This Site
Not sure about Postgre but SELECT TOP 10... should do the trick if you sort correctly
However about the second part: You might use a Right Join for this. Join the TOP 10 Result with the whole table data and use only the records not appearing on the left side. If you calculate the sum of those you should get your "Sum of the rest" result.
I assume that vw_my_top_10 is the view showing you the top 10 records. vw_all_records shows all records (including the top 10).
Like this:
SELECT SUM(a_field)
FROM vw_my_top_10
RIGHT JOIN vw_all_records
ON (vw_my_top_10.Key = vw_all_records.Key)
WHERE vw_my_top_10.Key IS NULL
I have 2 integer fields in a table "user": leg_count and leg_length. The first one stores the amount of legs of a user and the second one - their total length.
Each leg that belongs to user is stored in separate table, as far as typical internet user can have zero to infinity legs:
CREATE TABLE legs (
user_id int not null,
length int not null
);
I want to recalculate the statistics for all users in one query, so I try:
UPDATE users SET
leg_count = subquery.count, leg_length = subquery.length
FROM (
SELECT COUNT(*) as count, SUM(length) as length FROM legs WHERE legs.user_id = users.id
) AS subquery;
and get "subquery in FROM cannot refer to other relations of same query level" error.
So I have to do
UPDATE users SET
leg_count = (SELECT COUNT(*) FROM legs WHERE legs.user_id = users.id),
leg_length = (SELECT SUM(length) FROM legs WHERE legs.user_id = users.id)
what makes database to perform 2 SELECT's for each row, although, required data could be calculated in one SELECT:
SELECT COUNT(*), SUM(length) FROM legs;
Is it possible to optimize my UPDATE query to use only one SELECT subquery?
I use PostgreSQL, but I beleive, the solution exists for any SQL dialect.
TIA.
I would do:
WITH stats AS
( SELECT COUNT(*) AS cnt
, SUM(length) AS totlength
, user_id
FROM legs
GROUP BY user_id
)
UPDATE users
SET leg_count = cnt, leg_length = totlength
FROM stats
WHERE stats.user_id = users.id
You could use PostgreSQL's extended update syntax:
update users as u
set leg_count = aggr.cnt
, leg_length = aggr.length
from (
select legs.user_id
, count(*) as cnt
, sum(length) as length
from legs
group by
legs.user_id
) as aggr
where u.user_id = aggr.user_id
how to create a query if i need to include two aggregate function in select row and per each function i need different group by and where conditions
in my example i need to returns the playerName, and how many the player win the this can be checked if the results in table game result= first, and how many times he played
but do not know how to deal with two aggregate functions .
simply i want to join the result of this two queries
1.
select playeName,count(*)
from player,game
where player.playerId=game.playerId and result="first"
group by game.playerId
2.
select count(*)
from game, player
where game.playerId=player.playerId
group by game.playerId
the set of attributes for table game are
playerId , result
the set of attributes for table player are
playerName,playerId
any idea???
Use:
SELECT p.playername,
SUM(CASE WHEN g.result = 'first' THEN 1 ELSE 0 END),
COUNT(*)
FROM PLAYER p
JOIN GAME g ON g.playerid = p.playerid
GROUP BY p.playername
Along with solutions proposed by OMG Ponies and Bnjmn, you can also get desired results by using WITH ROLLUP
select result, count(*)
from game, player
where game.playerId=player.playerId
group by game.playerId, result WITH ROLLUP
Then, on client side, find records with result equals 'first' and and result is null(which is #games played).