You can read, say, the top N lines of the file and perform type inference on the column data to determine the type of the column. This is how it's done in the F

You can read, say, the top N lines of the file and perform type inference on the column data to determine the type of the column. This is how it's done in the F# "type provider" for CSV: https://fsharp.github.io/FSharp.Data/library/CsvProvider.html https://fsharp.github.io/FSharp.Data/library/CsvProvider.htm...