How to merge requests?

Question

SQL

There are many similar queries like "SELECT COUNT(*) FROM ... WHERE ..." Is it possible to combine them into one query? To return an array of numbers COUNT. Those. the data is taken from the same table, the WHERE condition just changes. For example, take some kind of table like: Group(id, name, owner_id). And you need to take the type of all groups where the owner_id is equal to either 1 or 2 or 3. More precisely, take the number of such groups. You don't need to capture the data yourself.

Answer 1

so do SELECT owner_id,COUNT(*) FROM ... GROUP BY owner_id

Answer 2

select count(*) cnt from test
union all
select count(*) cnt from test2

Answer 3

interest Ask.
I would dig in the direction of data aggregation and my function
https://docs.djangoproject.com/en/1.10/ref/models/...

Answer 4

select '<10', count(id)  from TBL where Id < 10
  union all 
  select '=10', count(id) from TBL where Id = 10
  union all 
  select '>10', count(id) from TBL where Id > 10