fread should not create data.tables with more than 2^31 rows
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Assessment
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Newbie friendliness
- 45/100
Research direction
Start with fread's handling of row counts and the fread documentation on field width and size limits. Define the behavior when an import exceeds R's supported row count, then verify that oversized inputs are stopped or limited with a warning and that the documentation explains the constraint.
Written by the indexing model from the issue text.
Description
I just imported a huge file with more than 2^31 rows using fread on a machine with 512 GB RAM. It worked great. Unfortunately, I couldn't do anything with the resulting data.table. Autoprinting or subsetting returned a "long vectors not supported yet" error, which isn't surprising.
I suggest to stop fread before the data.table gets too large. Maybe it could return (with a warning) as many rows as R supports.
The fread documentation mentions field width limits but I don't see a mention that R has a limit regarding the number of rows.
My solution was to use nrows and skip to import as two data.tables but that was after I wasted time with reading the whole file.
- Dominant language
- R
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- Merged PRs (30d)
- 4
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