I have a bunch of records containing key,value pairs.

I'd like to create a CSV file containing one row for each record.

However, each record doesn't necessarily contain exactly the same keys as the other records. So I'd like the column-headers to be a superset of all the keys. E.g.

{AB1 => 100, NN => 200, XYZ => 400}
{AB1 => 100, XYZ => 400, MM => 300}

[download]
--> 
"AB1","NN","XYZ","MM"
"100","200","400",""
"100","","400","300"

[download]
ie. 
AB1   NN       XYZ   MM
100   200      400   undef
100   undef    400   300

[download]
I could do this "manually" as it were, but can one do it directly (using Text::CSV) ie. without figuring out the superset of keys myself? In Text::CSV I see one can *read* tables with headers as hashes. But can one write them just as easily?

In reply to Writing hashes as records to a CSV file by Serene Hacker

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