如何在 SQL 中按某些列聚合而不是按其他列聚合

Question

|other|last|first|program|

|cat|Acker|Bob A|

|dog|Acker|Bob|B|

|reptile|Acker|Bob|A|

|cat|Birch|Patty|B|

|bunny|Calhoun|Peter|C|

BECOMES

|other|last|first|program|

|cat|Acker|Bob A|

|dog|Acker|Bob|B|

|cat|Birch|Patty|B|

|bunny|Calhoun|Peter|C|

How do you get the above to work? I'm a sql novice. I'm trying to get a total count of records by one field based on certain values in other fields but not others. In the above Tables, I basically want sql to pull out reptile Acker Bob A, because A is already represented as a program by Bob. But I don't want the following removed for Bob because these programs are represented exactly once:

cat Acker   Bob A
dog Acker   Bob B

I've tried this but I can't get it to work:

SELECT program, total, sum(program) as allTotal
FROM mytable
GROUP BY program
HAVING count(program) <= 1

I want my end result to look like this:

program total allTotal

A 2 5

B 1 5

C 1 5

Answer 1

Is this what you want?

select
    program,
    count(*) total,
    (select count(*) from mytable) all_total
from mytable
group by program

Answer 2

It sounds like you want

SELECT program, COUNT(distinct CONCAT(first, last)) AS total, (SELECT COUNT(*) FROM mytable) AS allTotal
FROM mytable
GROUP BY program

By only counting the distinct CONCAT(first, last) it will not count Bob twice in Program A.

The equivalent for some DBs without CONCAT :

SELECT program, COUNT(distinct first||last) AS total, (SELECT COUNT(*) FROM mytable) AS allTotal
FROM mytable
GROUP BY program