I am trying to write a query which as follow:
select distinct bsg.id as bsgId,
s.system_id as sysId,
g.code_no as gameNo,
u.user_name as nameOfUser,
s.score_code as scoreId,
p.name as cityOfGame
from score s
join scoreGr sg on sg.id = s.scoreGr_id
join bigScoreGr bsg on sg.bigScoreGr_id = bsg.id
join game g on bsg.fld_case_id = g.id
join user u on s.user_id = u.id
join system_number sn on g.id = sn.game_id
join system_doc sd on sd.system_number_id = sn.id
left join parameter p on sd.city_id = p.id
Until I have joined with parameter table, result is as expected. The result seems like below:
bsgId| sysId | gameNo | nameOfUser | scoreId
--------------------------------------------------
1234 | abcde | G-12 | admin | G-12/1/1
1235 | abcdf | G-15 | admin | G-15/1/3
1234 | abcdf | G-12 | user1 | G-12/1/8
1237 | abcdf | G-16 | user1 | G-16/2/4
However, parameter table is something big and system_doc has some null values in its city_id column. When I add the left join part of my query, it becomes like that:
bsgId| sysId | gameNo | nameOfUser | scoreId | city
--------------------------------------------------
1234 | abcde | G-12 | admin | G-12/1/1 | city1
1235 | abcdf | G-15 | admin | G-15/1/3 | city5
1235 | abcdf | G-15 | admin | G-15/1/3 |
1234 | abcdg | G-12 | user1 | G-12/1/8 | city4
1234 | abcdg | G-12 | user1 | G-12/1/8 |
1237 | abcdf | G-16 | user1 | G-16/2/4 |
I do not want rows like 3rd and 5th ones. To avoid these rows which has null in their city columns and "has the exact same data except city field" (I mean city can be null actually,as in the last row, but having row #2 makes row #3 useless, so I only want row #2) I have used distinct on(scoreId), but it did not worked since I have lost row #2 but not row #3.
How could I eliminate those duplicate rows which has null in their city fields? I hope my question is clear.
It's a postgresql bug.
left join parameter p on sd.city_id = p.id
Try this
left join parameter p on p.id = p.id
WHERE sd.city_id = p.id
(I have answered this so anyone looking for will now know about this bug)
It seems like you have a composite key. Try to mention all columns of composite key i.e. if you have primary key(pk1, pk2) then select * from table1 left join table2 on table1.pk1=table2.pk1 and table2.pk2=table2.pk2
Related
How can I use string_to_array or split_part on another column value.
I want do something like select * from tenants where id IN (select string_to_array(select ancestry from tenants where id = 39,'/'));
-[ RECORD 1 ]-------------+----------------------
id | 1
domain |
subdomain |
name | My Company
login_text |
logo_file_name |
logo_content_type |
logo_file_size |
logo_updated_at |
login_logo_file_name |
login_logo_content_type |
login_logo_file_size |
login_logo_updated_at |
ancestry |
divisible | t
description | Tenant for My Company
use_config_for_attributes | t
default_miq_group_id | 1
source_type |
source_id |
-[ RECORD 3 ]-------------+----------------------
id | 35
domain |
subdomain |
name | Tenant_2
login_text |
logo_file_name |
logo_content_type |
logo_file_size |
logo_updated_at |
login_logo_file_name |
login_logo_content_type |
login_logo_file_size |
login_logo_updated_at |
ancestry | 1
divisible | t
description | Tenant_2
use_config_for_attributes | f
default_miq_group_id | 36
source_type |
source_id |
-[ RECORD 7 ]-------------+----------------------
id | 39
domain |
subdomain |
name | Child_Teanant_202
login_text |
logo_file_name |
logo_content_type |
logo_file_size |
logo_updated_at |
login_logo_file_name |
login_logo_content_type |
login_logo_file_size |
login_logo_updated_at |
ancestry | 1/35
divisible | t
description | Child_Teanant_202
use_config_for_attributes | f
default_miq_group_id | 52
source_type |
source_id |
Use regex to enforce word boundaries:
select *
from tenants
where (select ancestry from tenants where id = 39)
~ ('\y' || id || '\y')
See live demo.
Without the word boundaries an id of 1 would match an ancestry of 123.
Note Postgres's unusual regex for word boundary \y, which elsewhere is \b.
There are two ways to solve this.
One is to simply unnest the elements of ancestry
select *
from tenants
where id in (select a.id::int
from tenants t2
cross join unnest(string_to_array(t2.ancestry, '/')) as a(id)
where t2.id = 39);
Converting the string to an array in order to be able to use the = ANY() operator is a bit tricky, because you need two levels of parentheses plus a type cast to an integer array to make that work:
select *
from tenants
where id = any ((select string_to_array(t2.ancestry, '/')
from tenants t2
where t2.id = 39)::int[]);
Online example
Lets suppose i have this table:
project |leader|coordination|staff |support |
---------|------|------------|-------------------|-----------|
project_a|Bob |{Alice} |{Terry,Mandy,James}|{Bob,Peter}|
project_b|Alice |{Terry, Bob}|{Mandy,James} |{Maggie} |
project_c|Maggie|{Bob} |{Terry,Peter} |{Alice,Bob}|
and i want to transform it to something like this:
person|project_1|role_1|project_2|role_2 |project_3|role_3 |project_4|role_4 |
------|---------|------|---------|------------|---------|-------|---------|------------|
Alice |project_b|leader|project_a|coordination|project_c|support| | |
Bob |project_a|leader|project_a|support |project_b|staff |project_c|coordination|
Terry...
Maggie...
...
Big thanks to #abelisto for pointing me in the right direction in the comments.
The problem with crosstab is, that i need the project also in the row:
SELECT *
FROM crosstab(
'
select
person,
project,
role
from
tmp_projects
cross join lateral (
select
\'leader\'::text as role, leader as person
union all
select
\'coordination\', x
from
unnest(coordination) as x
union all
select
\'staff\', x
from
unnest(staff) as x
union all
select
\'support\', x
from
unnest(support) as x) as t order by 1,2' -- needs to be "ORDER BY 1,2" here
, 'SELECT DISTINCT project FROM tmp_projects ORDER BY 1'
) AS ct ("Person" text, "Project_1" text,"Project_2" text,"Project_3" text);
#Abelisto had the correct idea and a solution could be:
create view tmp_view_projects_unnest as select
person,
row_number() OVER (PARTITION by person) AS rn,
project,
role
from
tmp_projects
cross join lateral (
select
'leader'::text as role, leader as person
union all
select
'coordination', x
from
unnest(coordination) as x
union all
select
'staff', x
from
unnest(staff) as x
union all
select
'support', x
from
unnest(support) as x) as t order by 1,2
person|rn|project |role |
------|--|---------|------------|
Alice | 1|project_a|leader |
Alice | 2|project_d|coordination|
Alice | 3|project_c|support |
Bob | 1|project_d|coordination|
Bob | 2|project_c|coordination|
Bob | 3|project_c|support |
Maggie| 1|project_c|leader |
Mandy | 1|project_d|leader |
Marry | 1|project_d|staff |
Peter | 1|project_d|support |
Peter | 2|project_c|staff |
Peter | 3|project_a|coordination|
Terry | 1|project_a|coordination|
Terry | 2|project_c|staff |
select tvp.person,
tvp.project as project_1, tvp.role as role_1 ,
tvp2.project as project_2, tvp2.role as role_2,
tvp3.project as project_3, tvp3.role as role_3,
tvp4.project as project_4, tvp4.role as role_4
from tmp_view_projects_unnest tvp
left join tmp_view_projects_unnest tvp2 on tvp2.person = tvp.person and tvp2.rn =2
left join tmp_view_projects_unnest tvp3 on tvp3.person = tvp.person and tvp3.rn =3
left join tmp_view_projects_unnest tvp4 on tvp4.person = tvp.person and tvp4.rn =4
where tvp.rn=1;
person|project_1|role_1 |project_2|role_2 |project_3|role_3 |project_4|role_4|
------|---------|------------|---------|------------|---------|------------|---------|------|
Alice |project_a|leader |project_d|coordination|project_c|support | | |
Bob |project_d|coordination|project_c|coordination|project_c|support | | |
Maggie|project_c|leader | | | | | | |
Mandy |project_d|leader | | | | | | |
Marry |project_d|staff | | | | | | |
Peter |project_d|support |project_c|staff |project_a|coordination| | |
Terry |project_a|coordination|project_c|staff | | | | |
Here's a crude example I've made up to illustrate what I want to achieve:
table1:
| Shop | Product | QuantityInStock |
| a | Prod1 | 13 |
| a | Prod3 | 13 |
| b | Prod2 | 13 |
| b | Prod3 | 13 |
| b | Prod4 | 13 |
table1 becomes:
| Shop | Product | QuantityInStock |
| a | Prod1 | 13 |
| a | Prod2 | 0 | -- new
| a | Prod3 | 13 |
| a | Prod4 | 0 | -- new
| b | Prod1 | 0 | -- new
| b | Prod2 | 13 |
| b | Prod3 | 13 |
| b | Prod4 | 13 |
In this example, I want to represent every Shop/Product combination
every Shop {a,b} to have a row with every Product {Prod1, Prod2, Prod3, Prod4}
QuantityInStock=13 has no significance, I just wanted a placeholder number :)
Use a calendar table cross join approach:
SELECT s.Shop, p.Product, COALESCE(t1.QuantityInStock, 0) AS QuantityInStock
FROM (SELECT DISTINCT Shop FROM table1) s
CROSS JOIN (SELECT DISTINCT Product FROM table1) p
LEFT JOIN table1 t1
ON t1.Shop = s.Shop AND
t1.Product = p.Product
ORDER BY
s.Shop,
p.Product;
The idea here is to generate an intermediate table containing of all shop/product combinations via a cross join. Then, we left join this to table1. Any shop/product combinations which do not have a match in the actual table are assigned a zero stock quantity.
I'd like to return IDs with different values between segments:
| id | segment | quantity |
|-------|-------------|----------|
| 12345 | Control - A | 1 |
| 12345 | Control - B | 1 |
| 98765 | Control - A | 0 |
| 98765 | Control - B | 1 |
Output:
| id |
|-------|
| 98765 |
I have tried CASE logic, partitioning, etc. but am wondering the optimal approach.
I find using the EXISTS clause to be the easiest to read in these types of cases, but the other answer with the self-join should also work just fine.
select distinct id
from t1 where exists
(select 1
from t1 t1_alias
WHERE t1.id = t1_alias.id and
t1.segment != t1_alias.segment and
t1.quantity != t1_alias.quantity)
;
Probably not the optimal approach, but you haven't mentioned it, I would try something like this:
select
distinct t1.id
from
table t1 inner join
table t2 on t1.id = t2.id and t1.quantity != t2.quantity and t1.segment != t2.segment
As the title says, I need to create a query where I SELECT all items from one table and use those items as expressions in another query. Suppose I have the main table that looks like this:
main_table
-------------------------------------
id | name | location | //more columns
---|------|----------|---------------
1 | me | pluto | //
2 | them | mercury | //
3 | we | jupiter | //
And the sub query table looks like this:
some_table
---------------
id | item
---|-----------
1 | sub-col-1
2 | sub-col-2
3 | sub-col-3
where each item in some_table has a price which is in an amount_table like so:
amount_table
--------------
1 | 1000
2 | 2000
3 | 3000
So that the query returns results like this:
name | location | sub-col-1 | sub-col-2 | sub-col-3 |
----------------------------------------------------|
me | pluto | 1000 | | |
them | mercury | | 2000 | |
we | jupiter | | | 3000 |
My query currently looks like this
SELECT name, location, (SELECT item FROM some_table)
FROM main_table
INNER JOIN amount_table WHERE //match the id's
But I'm running into the error more than one row returned by a subquery used as an expression
How can I formulate this query to return the desired results?
you should decide on expected result.
to get one-tp-many relation:
SELECT name, location, some_table.item
FROM main_table
JOIN some_table on true -- or id if they match
INNER JOIN amount_table --WHERE match the id's
to get one-to-one with all rows:
SELECT name, location, (SELECT array_agg(item) FROM some_table)
FROM main_table
INNER JOIN amount_table --WHERE //match the id's