Table:
0
A
B
C
D
E
1
city
position
Event
year
Score
2
Santiago de Compostela
1
Mixed Doubles
2004
15-12/15-9
3
Alicante
1
Men's singles
2007
21-10/21-16
4
Ibiza
1
Men's singles
2008
21-17/21-15
5
Alicante
1
Men's singles
2009
21-10/21-14
6
Huelva
1
Men's singles
2010
21-7/21-17
7
Huelva
1
Men's doubles
2010
14-21/21-17/21-12
8
Madrid
1
Men's singles
2011
21-17/21-12
9
Huesca
1
Men's singles
2012
21-12/21-12
10
Huesca
1
Men's doubles
2012
21-15/21-8
11
Aestrada
1
Men's singles
2013
21-13/21-15
12
Aestrada
1
Men's doubles
2013
21-12/21-14

Questions and formulas:
Question: How many years did he play in santiago de compostela?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:E1,A1="santiago de compostela"),4))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:E12,A2:A12="santiago de compostela"),4))
Level: medium