Multiple count based on dynamic criteria - sql

Question

I have two database for which I want to compare the amount of times a case appears.
TAB1:
ID Sequence
A2D 1
A2D 2
A2D 3
A3D 1
TAB2:
ID Sequence
A2D 1
A2D 2
A3D 1
A3D 2
Now, for this example, I am trying to get this result:
ID Table1 Table2
A2D 3 2
A3D 1 2
I have tried these code without any success:
SELECT R1.ID as ID, COUNT(R1.ID) as Table1,
COUNT(R2.ID) as Table2
FROM TAB1 AS R1, TAB2 AS R2
WHERE R1.ID = R2.ID
GROUP BY R1.ID
This one gave me wrong count values...
Also, this one simply crash:
select
(
select count(*) as Table1
from TAB1
where ID = R1.ID
),(
select count(*) as Table2
from TAB2
where ID= R1.ID
)
FROM TAB1 AS R1
As you can see though, I am trying to have my criteria dynamic. Most examples I found were including basic hard-coded criteria. But for my case, I want the query to look at my first table ID, count the amount of time it appears, do it for the 2nd table with the same ID, then move on to the next ID.
If my question lacks information or is confusing just ask me, I'll do my best to be more precise.
Thanks in advance !

Answer 1

Here I am using a UNION ALL as a subquery
SELECT ID, SUM(T1) AS Table1, SUM(T2) AS Table2
FROM
(SELECT ID, COUNT(ID) AS T1, 0 AS T2 FROM TAB1 GROUP BY ID
UNION ALL
SELECT ID, 0 AS T1, COUNT(ID) AS T2 FROM TAB2 GROUP BY ID)
GROUP BY ID
HAVING SUM(T1)>0 AND SUM(T2)>0

Answer 2

I used a different approach, but unfortunately I have to use two queries, i still don't know if they can be combined together. The first one is just for making sums of both tables, and combining the results:
SELECT "Tab1" AS [Table], Tab1.ID, Count(*) AS Total
FROM Tab1
GROUP BY "Tab1", Tab1.ID
UNION SELECT "Tab2" AS [Table], Tab2.ID, Count(*) AS Total
FROM Tab2
GROUP BY "Tab2", Tab2.ID
and, since Access supports Pivot queries, you can use this:
TRANSFORM Sum(qrySums.[Total]) AS Total
SELECT qrySums.[ID]
FROM qrySums
GROUP BY qrySums.[ID]
PIVOT qrySums.[Table];

Answer 3

Not sure if I understand your question, but you could try something like this:
SELECT DISTINCT t.ID,
(SELECT COUNT(ID) FROM R1 WHERE ID = t.ID) AS table1,
(SELECT COUNT(ID) FROM R2 WHERE ID = t.ID) AS table2
FROM table1 t

Answer 4

To get the desired results, I broke it down into two sub-queries (R1SQ and R2SQ) and a main UNION query - R1R2 that uses inner, left and right joins to include all row entries including those rows that do not appear in both tables:
R1SQ
SELECT R1.Builder, Count(R1.Builder) AS Table1
FROM R1
GROUP BY R1.Builder;
R2SQ
SELECT R2.Builder_E, Count(R2.Builder_E) AS Table2
FROM R2
GROUP BY R2.Builder_E;
R1R2
SELECT R1SQ.Builder, R1SQ.Table1, R2SQ.Table2
FROM R1SQ INNER JOIN R2SQ ON R1SQ.Builder = R2SQ.Builder_E
UNION
SELECT R1SQ.Builder, R1SQ.Table1, 0 AS Table2
FROM R1SQ LEFT JOIN R2SQ ON R1SQ.Builder = R2SQ.Builder_E
WHERE (((R2SQ.Builder_E) Is Null))
UNION
SELECT R2SQ.Builder_E, 0 AS Table1, R2SQ.Table2
FROM R1SQ RIGHT JOIN R2SQ ON R1SQ.Builder = R2SQ.Builder_E
WHERE (((R1SQ.Builder) Is Null))
ORDER BY R1SQ.Builder;