[GRASS-dev] [GRASS GIS] #1391: dbf driver: implicit duplicate
column names
GRASS GIS
trac at osgeo.org
Wed Jun 15 06:22:09 EDT 2011
#1391: dbf driver: implicit duplicate column names
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Reporter: mmetz | Owner: grass-dev@…
Type: defect | Status: new
Priority: normal | Milestone: 7.0.0
Component: Database | Version: svn-releasebranch64
Keywords: dbf driver | Platform: All
Cpu: All |
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The dbf driver in lib/external/shapelib limits the length of column names
to 10 characters. Longer names are silently truncated to 10 characters
without checking for duplicates. The dbf driver in db/drivers/dbf limits
the length of column names to 20 characters and passes these too long
names to lib/external/shapelib. This limit should be changed to 10
characters, otherwise column names longer than 10 characters with the
first 10 characters being identical will result in identical column names
in the dbf file. These identical column names create all sorts of
(cryptic) problems, unfortunately without any warning or error.
It may be necessary to add routines to create unambiguous column names, or
at least suggest alternative names to the user, e.g. as cnames option for
v.in.ogr. Currently, add_column() in db/drivers/dbf/column.c will fail in
case of duplicate column names with an error message but not a fatal
error.
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Ticket URL: <https://trac.osgeo.org/grass/ticket/1391>
GRASS GIS <http://grass.osgeo.org>
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