Hi this spec will help you resolve the query :
[
{
"operation": "shift",
"spec": {
"INS-2000_loop": {
"*": {
"HD-2300_loop": {
"*": {
"*": "L2300[#2].&"
}
},
"INS_*": "L2000.[#2].&",
"REF_*": "L2000.[#2].&",
"NM1-2100A_loop": "L2000.[#2].&"
}
}
}
},
{
"operation": "cardinality",
"spec": {
"L2300": {
"*": {
"*": "ONE"
}
}
}
}
]
Check this spec
[
{
"operation": "shift",
"spec": {
"readings": {
"*": {
"records": {
"*": {
"values": {
"@": "[].@(2,timestamp)"
}
}
}
}
}
}
}, {
"operation": "shift",
"spec": {
"*": {
"*": {
"@": "[]",
"$": "[&2].timestamp"
}
}
}
}
]