What PDF is
PDF describes a page: glyphs at coordinates, not rows and columns. A table in a PDF is a visual arrangement, not a data structure.
Reports, invoices, statements and anything sent to be read rather than processed.
What ASP is
A two-dimensional VBScript array with one assignment per cell.
Classic ASP applications.
What changes when you convert PDF to ASP
Every character in a text-based PDF carries its position on the page. Characters sharing a baseline are one row. Columns are found from the vertical strips no character ever occupies, which is why extraction works cleanly on a document laid out with spacing and badly on one laid out with ruled lines. A header repeated at the top of each page is detected and dropped rather than landing in the middle of the data.
Dimensioned to the exact size of the table, then filled cell by cell.
What carries over from PDF to ASP
PDF records 2 things about a table that ASP has no way to hold.
ASP wants a type for each column, and PDF does not record one, so each column is typed from what its values look like. A column of digits that should stay text - a zip code, a phone number, a leading-zero id - is the usual thing to check afterwards.
A line break inside a cell ends the row in ASP, so line breaks are replaced rather than carried through.
Anything visual in the PDF - weight, alignment, colour, column widths - has no counterpart in ASP and is dropped. The values are what survives.
This is the direction that recovers structure: PDF has no table in it to read, only an arrangement that looks like one, so the rows and columns are inferred rather than read.