Source array name: build
3 columns:
x - int64 - is attribute:false
y - int64 - is attribute:false
a - string - is attribute:true
=====
x y a
-----
0 0 a
0 1 b
0 2 c
1 0 d
1 1 e
1 2 f
2 0 123
2 1 456
2 2 789
