Is there a way, in SQL, to create an Id for 'linked groups'?
Source Table
+----+-----+
| Id | Id |
+----+-----+
| 1 | 2 |
| 1 | 3 |
| 2 | 3 |
| 4 | 5 |
+----+-----+
Desired Result Table
+----+-----+-----------+
| Id | Id | Group Id |
+----+-----+-----------+
| 1 | 2 | A |
| 1 | 3 | A |
| 2 | 3 | A |
| 4 | 5 | B |
+----+-----+-----------+
see Diagram
Related
Hi i have a table like this;
+----+----------+-------------+
| id | room_id | house_id |
+----+----------+-------------+
| 1 | 1 | 1 |
| 2 | 2 | 1 |
| 3 | 3 | 1 |
| 4 | 1 | 2 |
| 5 | 2 | 2 |
| 6 | 3 | 2 |
| 7 | 1 | 3 |
| 8 | 2 | 3 |
| 9 | 3 | 3 |
+----+-------+----------------+
and i want to create a view like this
+----+----------+-------------+
| id | house_id | rooms |
+----+----------+-------------+
| 1 | 1 | [1,2,3] |
| 2 | 2 | [1,2,3] |
| 3 | 3 | [1,2,3] |
+----+-------+----------------+
i tried many ways but i cant gruop them in one line
Thanks for any help.
You can use array_agg():
select house_id, array_agg(room_id order by room_id) as rooms
from t
group by house_id;
If you want the first column to be incremental, you can use row_number():
select row_number() over (order by house_id) as id, . . .
I have two tables 'Product' and 'product_Desc'
+-----------+-------------+
| ProductID | ProductName |
+-----------+-------------+
| 1 | A |
| 2 | B |
+-----------+-------------+
+----+-----------+-------------+-----------+
| Id | ProductID | ProductDec | SortOrder |
+----+-----------+-------------+-----------+
| 1 | 1 | Aero-pink | |
| 2 | 1 | Aero-white | |
| 3 | 1 | Aero-green | |
| 4 | 1 | Aero-Orange | |
| 5 | 2 | Baloon-1 | |
| 6 | 2 | Baloon-2 | |
| 7 | 2 | Baloon-3 | |
+----+-----------+-------------+-----------+
Now, what is the Sql code that can update 'sortOrder' column sequentially for each group of ProductID as shown below:
+----+-----------+-------------+-----------+
| Id | ProductID | ProductDec | SortOrder |
+----+-----------+-------------+-----------+
| 1 | 1 | Aero-pink | 1 |
| 2 | 1 | Aero-white | 2 |
| 3 | 1 | Aero-green | 3 |
| 4 | 1 | Aero-Orange | 4 |
| 5 | 2 | Baloon-1 | 1 |
| 6 | 2 | Baloon-2 | 2 |
| 7 | 2 | Baloon-3 | 3 |
+----+-----------+-------------+-----------+
Please note that these are sample tables, actual tables have thousands of records.
Would appreciate your help on this. Thank you
with cte
as
(
select SortOrder, row_number() over(partition by ProductID order by Id) as newPerProductOrder
from product_Desc
)
update cte
set SortOrder = newPerProductOrder
where (SortOrder <> newPerProductOrder or SortOrder is null)
So I have an accounts table in witch row may or may not have a parent account (0 means it doesn't have a parent):
+----+-----------+
| id | parent_id |
+----+-----------+
| 1 | 2 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 4 |
+----+-----------+
I was trying to add the top 3 parents for each row, so I would get something like this:
+----+-----------+----------+----------+----------+
| id | parent_id | parent_1 | parent_2 | parent_3 |
+----+-----------+----------+----------+----------+
| 1 | 2 | 2 | null | null |
| 2 | 0 | null | null | null |
| 3 | 1 | 2 | 1 | null |
| 4 | 3 | 2 | 1 | 3 |
| 5 | 4 | 2 | 1 | 3 |
+----+-----------+----------+----------+----------+
I figured I can do it with recursive queries, but I haven't managed to build a working query.
Any help would be appreciated.
I have a SQL table as following
--------------------------
| REPO | USER | FOLLOWER |
--------------------------
| A | 1 | 3 |
| A | 2 | 4 |
| A | 3 | 6 |
| B | 2 | 7 |
| B | 4 | 2 |
| C | 5 | 3 |
| C | 2 | 6 |
| C | 6 | 5 |
--------------------------
Now, I want to only those rows where USER follows another USER for
same REPO.
i.e. I want rows where elements in FOLLOWER is also in USER for same
REPO.
OUTPUT should be like...
--------------------------
| REPO | USER | FOLLOWER |
--------------------------
| A | 1 | 3 |
| B | 4 | 2 |
| C | 6 | 5 |
| C | 2 | 6 |
--------------------------
Thank You :)
One simple method uses exists:
select t.*
from t
where exists (select 1 from t t2 where t2.repo = t.repo and t2.follower = t.user);
Shouldn't the output actually be as follows, i.e. 4 rows?
--------------------------
| REPO | USER | FOLLOWER |
--------------------------
| A | 1 | 3 |
| B | 4 | 2 |
| C | 6 | 5 |
| C | 2 | 6 |
--------------------------
I have this table that is already sorted but I want it to only display the maximum values... so instead of this table:
+------+-------+
| id | value |
+------+-------+
| 1 | 3 |
| 5 | 3 |
| 4 | 3 |
| 9 | 2 |
| 8 | 2 |
| 3 | 2 |
| 2 | 1 |
| 6 | 1 |
| 7 | 1 |
+------+-------+
I want this:
+------+-------+
| id | value |
+------+-------+
| 1 | 3 |
| 5 | 3 |
| 4 | 3 |
+------+-------+
I'm using SQLite. thanks for any help.
You can do this using a subquery. Here is one way:
select t.*
from t
where t.value = (select max(value) from t);