How to combine rows with same ID in Google Sheets?

Question

I\'m trying to merge rows with same IDs in Google Sheets

From:

ID     | Category
Augur  | A1
Augur  | A2
Augur  | A3
Augur1 | A1
Augur1 | A2
Augur1 | A3
         


        

Answer 1

=ARRAYFORMULA(QUERY({INDEX(QUERY(A1:B, 
 "select A,count(A) where A is not null group by A pivot B", 0), , 1),
 REGEXREPLACE(TRIM(TRANSPOSE(QUERY(TRANSPOSE(IF(ISNUMBER(QUERY(A1:B, 
 "select count(A) where A is not null group by A pivot B", 0)), INDEX(QUERY({A1:A,B1:B&";"},
 "select count(Col1) where Col1 is not null group by Col1 pivot Col2 offset 1", 0), 1,), ))
 , , 999^99))), ";$", )}, "offset 1", 0))