How can I find the amount of keys that are related to one key?

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Hello. newbie here.

I am trying to find out how many keys.
For example,

( Animals ) PK ---- ( Enclosure ) Fk
 Gorilla ------------ North
Chimps ------------- North
Dogs --------------- North
Cats -------------- South
Rabbits ------------ East

Here 3 animals are in 1 Enclosure location of the North.
1 animal in South and 1 in East.

How can I count like that, when the database is huge?
is there a command for it?

What I have tried:

i tried using

SQL

Select distinct (animal.enclosure_enclosureID ) from mydb.animals ;

but this shows
all the unique enclosure IDs.
How can I find how many of the animal_ID are related to each of the enclosure ID?

Posted 4-Dec-21 3:54am

Bonzowo

Updated 4-Dec-21 4:29am

PIEBALDconsult

v2

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PIEBALDconsult 4-Dec-21 10:05am

I don't think you provide enough information.
Use Improve question to add more detail.

Dave Kreskowiak 4-Dec-21 10:23am

It's not entirely clear what you're asking. "Counting keys" is not a thing.

Are you looking for the total number of animals? The total number of enclosures? The total number of animals in each enclosure? ... What?

Bonzowo 4-Dec-21 10:24am

Total number of animals in each enclosure. Yeah

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Dave Kreskowiak · Answer 1 · 2021-12-04T04:29:00

Solution 1

This is your homework assignment so you're not going to get a straight up answer.

You'll get a hint though. You don't need DISTINCT. You need GROUP BY.

Posted 4-Dec-21 4:29am

Dave Kreskowiak