How do I use a variable in an object path with JSONata

I'm using the code below in a Change Node using JSONata to structure MySQL data to send to a graph node. Is there any way for me to add the column name into the object path from a flow variable?

[
{
"series": ["B"],
"labels": [payload.time],
"data": [[payload.AvgAirTemp1]]
}
]

I've tried changing to the line below but it didn't work

"data": [[payload.$flowContext('columnName')]]

Thanks

Hi @Jamie

try:

"data": [[$lookup(payload,$flowContext('columnName')) ]]

Thank you. That is what I needed.