Table:
0
A
B
C
D
E
1
candidate id
qualification
assessment date
asessment outcome code
candidate assessments
2
111
A
2010-04-07 11:44:34
Pass
3
121
B
2010-04-17 11:44:34
Pass
4
131
D
2010-04-05 11:44:34
Fail
5
141
C
2010-04-06 11:44:34
Pass
6
151
B
2010-04-09 11:44:34
Pass

Questions and formulas:
Question: Dates and ids for candidates who passed assessment.
Formula: LET(query1,FILTER(A1:E1,D1="pass"),UNIQUE(CHOOSECOLS(query1,1,3)))
Formula2: LET(query1,FILTER(A2:E6,D2:D6="pass"),UNIQUE(CHOOSECOLS(query1,1,3)))
Level: hard
Question: the ids of candidates who pass the assessment
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,D1="pass"),1))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E6,D2:D6="pass"),1))
Level: medium