SQL - Row For Each Criteria - Access - sql

Question

I am trying to create a query that will take a list of data, and give me N rows each time it meets a criteria.
Say I have the following data:
ID | Type
1 | Vegetables
2 | Vegetables
3 | Vegetables
4 | Fruits
5 | Fruits
6 | Meats
7 | Dairy
8 | Dairy
9 | Dairy
10 | Dairy
And what I want is:
Type
Dairy
Dairy
Dairy
Fruits
Fruits
Meats
Meats
Vegetables
Vegetables
The criteria I have is that for every 2 of each Type I count it as a "whole" value. If there is anything more than a whole value, round up to the nearest whole number. So, the Vegetables Type rounds up from 1.5 to 2 rows and the Dairy Type stays at 2 rows.
Then I want to add a row to every Type that is not the last type in the set (Which is why Vegetables only has two rows), perhaps with another column denomination showing that it was the added row.

Answer 1

This query will return every type along with the number of times that it has to be repeated:
SELECT Type, tot+IIf(Type=(SELECT MAX(Type) FROM tablename),0,1) AS Rep
FROM (SELECT tablename.Type, -Int(-Count([tablename].[ID])/2) AS tot
FROM tablename
GROUP BY tablename.Type
) AS s;
then my idea is to use a table named [times] that contains every number repeated n times:
n
---
1
2
2
3
3
3
...
and then your query could be like this:
SELECT s.*
FROM (
SELECT Type, tot+IIf(Type=(SELECT MAX(Type) FROM tablename),0,1) AS rep
FROM (SELECT tablename.Type, -Int(-Count([tablename].[ID])/2) AS tot
FROM tablename
GROUP BY tablename.Type
) AS s1) s INNER JOIN times ON s.rep=times.n

Answer 2

So you want to count the records, divide by 2, round up and then add 1.
--Create a temporary table with all numbers from 1 to 1024.
declare #Numbers table
(
MaxQty INT IDENTITY(1,1) PRIMARY KEY CLUSTERED
)
WHILE COALESCE(SCOPE_IDENTITY(), 0) <= 1024
BEGIN
INSERT #Numbers DEFAULT VALUES
END
--First get the count of records
SELECT [Type], Sum(1) as CNT
INTO #TMP1
FROM MyTable
Group By [Type]
--Now get the number of times the record should be repeated, based on this formula :
-- count the records, divide by 2, round up and then add 1
SELECT [Type], CNT, CEILING((CNT/2)+1) as TimesToRepeat
INTO #TMP2
FROM #TMP1
--Join the #TMP2 table with the #Numbers table so you can repeat your records the
-- required number of times
SELECT A.*
from #TMP2 as A
join #Numbers as B
on B.MaxQty <= A.TimesToRepeat
Not pretty, but it should work. This still doesn't account for the last type in the set, I'm a little stumped by that part.