I have a table where everything that has the same classification_id and application_id have the same group_id.
id |classification_id |application_id |authorisation_id |group_id |
------------------------------------ ------------------------------------ ------------------------------------ ------------------------------------ ------------------------------------
54f614f3-7582-4ae9-a07e-5ff6d29e7a3b|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
a01571a1-4f04-4ff9-9a7b-3a720736b9ec|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
3e18f2d0-4d5f-41b3-baf5-ba0feac8f43e|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
b2ebe2ee-ffed-4e32-8abe-cd8b7d400646|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
ef01e6f7-f6ad-4d4d-b129-9c756734bef5|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
7d340811-b679-49fd-bdd6-32a1bb9bbfed|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
c45d7bb6-2146-48d0-a804-929cc42484cd|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
ddec5929-a08f-4f48-97f8-ccc2b85531ac|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
ae9edbb2-def3-4c4e-9a27-72454a09e146|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
3a3fd904-1988-4f8c-bf27-8cdf349b8431|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
27c669b9-763c-49cf-887a-b9b1f85dc1ab|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
03820732-32c4-4cd4-910b-4e27fdd44bdf|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|8e563f95-ff0c-41e7-b211-d5ac6f78d056|
I've managed to sort out subgroups of this group by authorisation_id and I've created a group_helper which basically shows my end goal - from this data set I want to get three different groups:
id |classification_id |application_id |authorisation_id |group_id |group_helper|
------------------------------------ ------------------------------------ ------------------------------------ ------------------------------------ ------------------------------------ ------------
54f614f3-7582-4ae9-a07e-5ff6d29e7a3b|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 2|
a01571a1-4f04-4ff9-9a7b-3a720736b9ec|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 2|
3e18f2d0-4d5f-41b3-baf5-ba0feac8f43e|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 2|
b2ebe2ee-ffed-4e32-8abe-cd8b7d400646|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 2|
ef01e6f7-f6ad-4d4d-b129-9c756734bef5|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 3|
7d340811-b679-49fd-bdd6-32a1bb9bbfed|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 3|
c45d7bb6-2146-48d0-a804-929cc42484cd|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 3|
ddec5929-a08f-4f48-97f8-ccc2b85531ac|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|8e563f95-ff0c-41e7-b211-d5ac6f78d056| 3|
ae9edbb2-def3-4c4e-9a27-72454a09e146|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
3a3fd904-1988-4f8c-bf27-8cdf349b8431|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
27c669b9-763c-49cf-887a-b9b1f85dc1ab|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
03820732-32c4-4cd4-910b-4e27fdd44bdf|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
Now, I want each of those groups to have a different group_id. I don't have to update the one which has group_id = NULL since it is already unique. Now I want to give every row that has group_helper = 2 same (but different from those where group_id = NULL) UUID, every row that has group_helper = 3 same UUID (but different from those which have group_id = NULL or 2) and so on. This has to work on n amount of group_helper values because there can be much more than maximum 2.
So my end goal would look like this:
id |classification_id |application_id |authorisation_id |group_id |group_helper|
------------------------------------ ------------------------------------ ------------------------------------ ------------------------------------ ------------------------------------ ------------
54f614f3-7582-4ae9-a07e-5ff6d29e7a3b|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|fd3e63d1-d59c-477f-b58b-3ae3726c7992| 2|
a01571a1-4f04-4ff9-9a7b-3a720736b9ec|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|fd3e63d1-d59c-477f-b58b-3ae3726c7992| 2|
3e18f2d0-4d5f-41b3-baf5-ba0feac8f43e|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|fd3e63d1-d59c-477f-b58b-3ae3726c7992| 2|
b2ebe2ee-ffed-4e32-8abe-cd8b7d400646|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|fd3e63d1-d59c-477f-b58b-3ae3726c7992| 2|
ef01e6f7-f6ad-4d4d-b129-9c756734bef5|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|ed3ff96c-2f93-4182-8e4f-4594cb20cbb6| 3|
7d340811-b679-49fd-bdd6-32a1bb9bbfed|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|ed3ff96c-2f93-4182-8e4f-4594cb20cbb6| 3|
c45d7bb6-2146-48d0-a804-929cc42484cd|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|ed3ff96c-2f93-4182-8e4f-4594cb20cbb6| 3|
ddec5929-a08f-4f48-97f8-ccc2b85531ac|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|ed3ff96c-2f93-4182-8e4f-4594cb20cbb6| 3|
ae9edbb2-def3-4c4e-9a27-72454a09e146|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|a4edd12d-c19e-4e0d-badd-d3cf5e6d6d82|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
3a3fd904-1988-4f8c-bf27-8cdf349b8431|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|25a7e1f7-4d8c-4e12-a10f-3654d7ef5ee9|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
27c669b9-763c-49cf-887a-b9b1f85dc1ab|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|302b23f1-ce57-4219-bcae-7bdbc3b86cb4|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
03820732-32c4-4cd4-910b-4e27fdd44bdf|63a7b151-2b8d-4b6a-b9a1-108a80ae4cdf|cd3d597b-25d1-4b4b-92f0-2ad8fcb4698c|5e3bce60-b0d8-436c-9d33-b3a1d4c9a308|8e563f95-ff0c-41e7-b211-d5ac6f78d056| |
CodePudding user response：
You can create a CTE which generates new group_id, selecting a single value for each group_helper column, then use update ... from .... (see demo)
with grouper(helper, gid) as
(select distinct on (group_helper)
group_helper
, gen_random_uuid()
from sometable
where group_helper is not null
order by group_helper
) --select * from grouper
update sometable
set group_id = gid
from grouper
where helper = group_helper;