【问题】
This is how my json looks like:
{
“data” :
[
{ “f1” : “v1”,
“f2” : “v2”,
“group” : [
{ “f3” : “x1”,
“f4” : “y1”,
“f5” : “z1”
},
{ “f3” : “x1”,
“f4” : “y2”,
&nbs