[GRASS5] Abstract access to data: problems

Thierry Laronde tlaronde at polynum.com
Fri Oct 31 06:33:21 EST 2003


Paul has applied my patches for pg.in.dbf. These should solve the 
problems related in #2150 and #2098 (numeric values truncated to
REAL that is to 6 digits) but...

The problem is that if I have indeed changed the REAL definition of
the decimal field to NUMERIC for commands passed to PostgreSQL, I
have let as is the manipulations done by the DBF access library.

What we see here is that, I suppose because of the use of "generic"
functions (generic access to distinct data), we use not the raw text
data extract from the DBF text fields, but the text translated from
binary data translated from scanning the DBF text! In short: through
multiple conversions, here unneeded, we loose information and in some
cases the conversion of the "numeric" DBF values to double and then
back to string will still give a result that is not exact.

The solution is to suppress all the unneeded manipulations. But the
problem seen here may be seen elsewhere.

What do others think?
Thierry Laronde (Alceste) <tlaronde at polynum.org>
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