Perhaps I do not understand something, but if you know how many records you will want from the file, my choice would be to create an array of random numbers, then sort the array. Then read the file sequentially, selecting the records determined by the list of random numbers.

HTH

Enjoy!
Dageek

In reply to Re: Approach to efficiently choose a random line from a large file by johndageek
in thread Approach to efficiently choose a random line from a large file by Your Mother

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