MS Access query-String aggregation - ms-access

Question

Looking for query in MS Access for below question-
Following is my data set where last row is with NULL in Value column. Also by doing Max(Value) for each Name+Office+Person+Category, I have extracted this data to avoid multiple rows with value
ID Name Office Person Category Value
1 FMR Americas Ben Global 7
1 FMR London Ben Global 5
1 FMR London Ben Overall 4.2
156 Asset London Ben Global 13
156 Asset London Ben Overall
157 WSR Paris Zen Global 2
My Expected result set is as below- I am expecting cross mark or any indicator which will show that for ID,Name,Office,person combination has value for Global/Overll categories or not in single row. I know it's somewhat of similar to "String aggregation"
ID Name Office Person Global Overall
1 FMR Americas Ben X
1 FMR London Ben X X
156 Asset London Ben X
157 WSR Paris Zen X
Appreciate your inputs..

Answer 1

I played around with this a little. I created two select queries Global and Overall
Global
SELECT ID, Name, Office, Person, Category AS Global
FROM [YourTable]
WHERE Category="Global" AND Value IS NOT NULL
Overall
SELECT ID, Name, Office, Person, Category AS Overall
FROM [YourTable]
WHERE Category="Overall" AND Value IS NOT NULL
Then I created a new query to join the select queries
SELECT g.ID, g.Name, g.Office, g.Person, Global, Overall
FROM Global g
LEFT JOIN Overall o ON g.ID = o.ID AND g.Name = o.Name AND g.Office = o.Office AND g.Person = o.Person
Hope this helps.

Answer 2

First, get a list of unique id/name/office combinations:
SELECT DISTINCT ID, Name, Office, Person
FROM TableName
Next, create subqueries for each category:
For Global:
SELECT ID, Name, Office, Person
FROM TableName
WHERE Category="Global"
For Overall:
SELECT ID, Name, Office, Person
FROM TableName
WHERE Category="Overall"
Finally, left join the subqueries to the main query, and use an expression to show the X:
SELECT DISTINCT ID, Name, Office, Person
Iif(Global.ID Is Not Null, "X") AS IsGlobal,
Iif(Overall.ID Is Not Null, "X") AS IsOverall
FROM (TableName
LEFT JOIN (
SELECT ID, Name, Office, Person
FROM TableName
WHERE Category="Global"
) AS Global
ON TableName.ID=Global.ID
AND TableName.Name=Global.Name
AND TableName.Office=Global.Office
AND TableName.Person=Global.Person)
LEFT JOIN (
SELECT ID, Name, Office, Person
FROM TableName
WHERE Category="Overall"
) AS Overall
ON TableName.ID=Overall.ID
AND TableName.Name=Overall.Name
AND TableName.Office=Overall.Office
AND TableName.Person=Overall.Person
It may be easier for you to save the subqueries as Access queries and reference the saved queries by name, instead of including the whole subquery in this query.