I have the same issue, and have gone through the reply and ensured everything is OK…but still the problem. My file is 2,400 rows and 16 columns, so even all those are nowhere near the 250,000 records. It’s a CSV file, and I’m working on a Mac (if that makes a difference).
This could be dependent on the workbook editor you’re using, or the data source itself. It’s possible to hide data in rows that wouldn’t be visible to the end user. When an anomaly like this occurs, any data (including “hidden” data) in a row is counted as a brand-new row.
If you used Excel to originally prepare the .csv, place the cursor anywhere where there’s data you can see, then hit Ctrl + End to go to the last cell in the table. If you’re taken 250K+ rows away, then that’s what’s going on with your .csv.
You can try two immediate steps:
1) With your existing .csv, select all empty-looking columns, and delete those. Repeat for rows. Afterwards, reattempt the import. The deletes should get rid of any hidden data.
2) If that was unsuccessful, open a plain text editor, like Notepad. Copy and paste ONLY the data you can see from your spreadsheet editor, into the text editor. Close the spreadsheet editor after pasting. Then, copy the text from the plain text editor and paste it into a brand-new workbook, and save as .csv. Reattempt the import afterwards.
Thanks for this - very useful, and worked a treat It was to do with the hidden data, which the Ctrl+End solution highlighted, and from that point on it became a simple solution to execute. Much appreciated, thanks.
For the future, here is a CSV file checker that you may find helpful, which checks for these types of things (maximum number of columns/rows, file type, encoding, empty columns, etc.) to help you avoid errors during the import process. Hope it helps!