I have a table which has records in array. Also there is another table which have single string records. I want to get records which have multiple occurrences in another table. Following are tables;
Vehicle
veh_id | vehicle_types
-------+---------------------------------------
1 | {"byd_tang","volt","viper","laferrari"}
2 | {"volt","viper"}
3 | {"byd_tang","sonata","jaguarxf"}
4 | {"swift","teslax","mirai"}
5 | {"volt","viper"}
6 | {"viper","ferrariff","bmwi8","viper"}
7 | {"ferrariff","viper","viper","volt"}
vehicle_names
id | vehicle_name
-----+-----------------------
1 | byd_tang
2 | volt
3 | viper
4 | laferrari
5 | sonata
6 | jaguarxf
7 | swift
8 | teslax
9 | mirai
10 | ferrariff
11 | bmwi8
I have a query which can give output what I expect but its not optimal and may be its expensive query.
This is the query:
select veh_name
from vehicle_names dsb
where (select count(*) from vehicle dsd
where dsb.veh_name = ANY (dsd.veh_types)) > 1
The output should be:
byd_tang
volt
viper
One option would be an aggregation query:
SELECT
vn.id,
vn.veh_name
FROM vehicle_names vn
INNER JOIN vehicle v
ON vn. veh_name = ANY (v.veh_types)
GROUP BY
vn.id,
vn.veh_name
HAVING
COUNT(*) > 1;
This only counts a vehicle name which appears in two or more records in the other table. It would not pick up, for example, a single vehicle record with the same name appearing two or more times.
Related
Basically each user has a team, and each team has 11 players, so whenever a player scores they earn some points. Now is there a automated way to do this -
As in when there is a update/entry in the USER_TEAM_PLAYERS table, summate the points of all players to the USER_TEAM table for the corresponding user in some column (in this case TEAM_TOTAL column).
I have two tables:
USER_TEAM with columns USER_ID, TEAM_TOTAL
USER_TEAM_PLAYERS with columns PLAYER_NAME, PLAYER_POINTS, USER_ID
Example:
TABLE - USER_TEAM
USER_ID | TEAM_TOTAL
---------------------
1 | 40
2 | 50
TABLE - USER_TEAM_PLAYERS
PLAYER_NAME | PLAYER_POINTS | USER_ID
-------------------------------------
Adam | 10 | 1
Alex | 30 | 1
Botas | 40 | 2
Pepe | 5 | 2
Diogo | 5 | 2
The first table should be only a view of the second one
CREATE VIEW USER_TEAM2 AS
SELECT USER_ID, SUM(PLAYER_POINTS) AS TEAM_TOTAL
FROM USER_TEAM_PLAYERS
GROUP BY USER_ID
ORDER BY USER_ID;
Doing this, you have no duplicate data and a view can be in SELECT, ... like a table.
Nota 1 : I used the name USER_TEAM2 because your first table still exists but you can delete it.
Nota 2 : If you want to have some specific data to the TEAM_TABLE, keep the 2 names, and modifify your view as needed by adding some fields with a JOIN of this first table.
I want to be able to filter out groups where the values aren't the same. When doing the query:
SELECT
category.id as category_id,
object.id as object_id,
object.value as value
FROM
category,
object
WHERE
category.id = object.category
We get the following results:
category_id | object_id | value
-------------+-----------+-------
1 | 1 | 1
1 | 2 | 2
1 | 3 | 2
2 | 4 | 3
2 | 5 | 2
3 | 6 | 1
3 | 7 | 1
The goal: Update the query so that it yields:
category_id
-------------
1
2
In other words, find the categories where the values are different from the others in that same category.
I have tried many different methods of joining, grouping and so on, to no avail.
I know it can be done with multiple queries and then filter with a little bit of logic, but this is not the goal.
You can use aggregation:
SELECT o.category as category_id
FROM object o
GROUP BY o.category
HAVING MIN(o.value) <> MAX(o.value);
You have left the FROM clause out of your query. But as written, you don't need a JOIN at all. The object table is sufficient -- because you are only fetching the category id.
I have trouble with a complex ordering problem. I have following example data:
table "categories"
id | frequency
1 | 0
2 | 4
3 | 0
table "entries"
id | category_id | type
1 | 1 | a
2 | 1 | a
3 | 1 | a
4 | 2 | b
5 | 2 | c
6 | 3 | d
I want to put entries rows in an order so that category_id,
and type are distributed evenly.
More precisely, I want to order entries in a way that:
category_ids that refer to a category that has frequency=0 are
distributed evenly - so that a row is followed by a different category_id
whenever possible. e.g. category_ids of rows: 1,2,1,3,1,2.
Rows with category_ids of categories with frequency<>0 should
be inserted from ca. the beginning with a minimum of frequency rows between them
(the gaps should vary). In my example these are rows with category_id=2.
So the result could start with row id #1, then #4, then a minimum of 4 rows of other
categories, then #5.
in the end result rows with same type should not be next to each other.
Example result:
id | category_id | type
1 | 1 | a
4 | 2 | b
2 | 1 | a
6 | 3 | d
.. some other row ..
.. some other row ..
.. some other row ..
5 | 2 | c
entries are like a stream of things the user gets (one at a time).
The whole ordering should give users some variation. It's just there to not
present them similar entries all the time, so it doesn't have to be perfect.
The query also does not have to give the same result on each call - using
random() is totally fine.
frequencies are there to give entries of certain categories a higher
priority so that they are not distributed across the whole range, but are placed more
at the beginning of the result list. Even if there are a lot of these entries, they
should not completely crowd out the frequency=0 entries at the beginning, through.
I'm no sure how to start this. I think I can use window functions and
ntile() to distribute rows by category_id and type.
But I have no idea how to insert the non-0-category-entries afterwards.
I am trying to make a drop down picker in an Access database to display all the primary keys not used, in this case a date that is limited to the first of the month.
I have 2 tables that are for this use
tblReport
pk date | Data for this record |
05/01/13 | stuff
06/01/13 | stuff
07/01/13 | stuff
08/01/13 | stuff
and
tblFutureDates
pk date | an index
05/01/13 | 1
06/01/13 | 2
07/01/13 | 3
08/01/13 | 4
09/01/13 | 5
10/01/13 | 6
11/01/13 | 7
12/01/13 | 8
I want a query that looks at these two tables and returns the dates that are in the second table that aren't in the first one. I have tried some joins but cannot figure it out. This is what I have thus far:
SELECT tblFutureDates.FutureDate
FROM tblFutureDates RIGHT JOIN tblReport
ON tblFutureDates.FutureDate = tblReport.ReportMonth;
and that returns:
05/01/13
06/01/13
07/01/13
08/01/13
Thanks
This selects dates from tblFutureDates that are NOT IN tblReport
SELECT tblFutureDates.FutureDate
FROM tblFutureDates
WHERE tblFutureDates.FutureDate
NOT IN (SELECT tblReport.ReportMonth FROM tblReport)
You can also use LEFT JOIN WHERE IS NULL and NOT EXISTS for more information about all 3 see this post.
i have a table like this one:
--------------------------------
id | name
--------------------------------
1 | aa
2 | aa
3 | aa
4 | aa
5 | bb
6 | bb
... one million more ...
and i like to obtain an arbitrary number of rows in a pre defined sequence and the other rows ordered by their name. e.g. in another table i have a short sequence with 3 id's:
sequ_no | id | pos
-----------------------
1 | 3 | 0
1 | 1 | 1
1 | 2 | 2
2 | 65535 | 0
2 | 45 | 1
... one million more ...
sequence 1 defines the following series of id's: [ 3, 1, 2]. how to obtain the three rows of the first table in this order and the rest of the rows ordered by their name asc?
how in PostgreSQL and how in mySQL? how would a solution look like in hql (hibernate query language)?
an idea i have is to first query and sort the rows which are defined in the sequence and than concat the other rows which are not in the sequence. but this involves tow queries, can it be done with one?
Update: The final result for the sample sequence [ 3, 1, 2](as defined above) should look like this:
id | name
----------------------------------
3 | aa
1 | aa
2 | aa
4 | aa
5 | bb
6 | bb
... one million more ...
i need this query to create a pagination through a product table where part of the squence of products is a defined sequence and the rest of the products will be ordered by a clause i dont know yet.
I'm not sure I understand the exact requirement, but won't this work:
SELECT ids.id, ids.name
FROM ids_table ids LEFT OUTER JOIN sequences_table seq
WHERE ids.id = seq.id
ORDER BY seq.sequ_no, seq.pos, ids.name, ids.id
One way: assign a position (e.g. 0) to each id that doesn't have a position yet, UNION the result with the second table, join the result with the first table, and ORDER BY seq_no, pos, name.