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v.db.dropcolumn(1grass)


NAME

   v.db.dropcolumn  - Drops a column from the attribute table connected to
   a given vector map.

KEYWORDS

   vector, attribute table, database

SYNOPSIS

   v.db.dropcolumn
   v.db.dropcolumn --help
   v.db.dropcolumn   map=name    [layer=string]    columns=name[,name,...]
   [--help]  [--verbose]  [--quiet]  [--ui]

   Flags:
   --help
       Print usage summary

   --verbose
       Verbose module output

   --quiet
       Quiet module output

   --ui
       Force launching GUI dialog

   Parameters:
   map=name [required]
       Name of vector map
       Or data source for direct OGR access

   layer=string
       Layer number or name
       Vector  features can have category values in different layers. This
       number determines which layer to use. When  used  with  direct  OGR
       access this is the layer name.
       Default: 1

   columns=name[,name,...] [required]
       Name of attribute column(s) to drop

DESCRIPTION

   v.db.dropcolumn  drops a column from the attribute table connected to a
   given vector map.  It  automatically  checks  the  connection  for  the
   specified layer. v.db.dropcolumn omits to delete the 'cat' column which
   is relevant to keep the connection between vector map and table.

NOTES

   v.db.dropcolumn is a front-end to db.execute to allow easier usage.

   The existing database connection(s) can be verified with v.db.connect.

EXAMPLES

   Dropping a column:
   g.copy vect=roadsmajor,myroads
   v.info -c myroads
   v.db.dropcolumn myroads column=SHAPE_LEN
   v.info -c myroads

SEE ALSO

    db.connect, db.dropcolumn, db.execute,  v.db.addcolumn,  v.db.connect,
   v.db.droptable, v.db.select, v.db.update
   GRASS SQL interface

AUTHOR

   Markus Neteler

   Last changed: $Date: 2011-11-08 13:24:20 -0800 (Tue, 08 Nov 2011) $

SOURCE CODE

   Available at: v.db.dropcolumn source code (history)

   Main  index  | Vector index | Topics index | Keywords index | Graphical
   index | Full index

    2003-2016 GRASS Development Team, GRASS GIS 7.2.0 Reference Manual



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