Python - CSV: Large file with rows of different lengths

Posted by dassouki on Stack Overflow See other posts from Stack Overflow or by dassouki
Published on 2010-03-31T00:56:59Z Indexed on 2010/03/31 1:03 UTC
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python-csv

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csv

In short, I have a 20,000,000 line csv file that has different row lengths. This is due to archaic data loggers and proprietary formats. We get the end result as a csv file in the following format. MY goal is to insert this file into a postgres database. How Can I do the following:

Keep the first 8 columns and my last 2 columns, to have a consistent CSV file
Add a Column to the file.

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0, img_id.jpg, -50

1, 2, 3, 4, 5, 0,0,0,0,0,0,0,0,0,0,0 img_id.jpg, -50

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