Provided by: grass-doc_8.3.0-1_all bug

NAME

       v.external.out  - Defines vector output format.

KEYWORDS

       vector, export, output, external, OGR, PostGIS

SYNOPSIS

       v.external.out
       v.external.out --help
       v.external.out  [-frpg]  [output=string]   [format=string]   [options=string[,string,...]]
       [loadsettings=name]     [savesettings=name]     [--overwrite]     [--help]     [--verbose]
       [--quiet]  [--ui]

   Flags:
       -f
           List supported formats and exit

       -r
           Cease using OGR/PostGIS, revert to native output and exit

       -p
           Print current status

       -g
           Print current status in shell script style

       --overwrite
           Allow output files to overwrite existing files

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       output=string
           Name of output directory or OGR or PostGIS data source
           Examples:
                   ESRI Shapefile: directory containing a shapefile
                   MapInfo File: directory containing a mapinfo file
                   PostGIS database: connection string, eg. ’PG:dbname=db user=grass’

       format=string
           Format for output vector data
           Options:  AmigoCloud,  BAG, CSV, Carto, DGN, DXF, ESRI_Shapefile, Elasticsearch, FITS,
           FlatGeobuf,  GML,  GPKG,  GPSBabel,  GPX,  GeoJSON,  GeoJSONSeq,  GeoRSS,  Geoconcept,
           Interlis_1,  Interlis_2,  JML,  KML, LIBKML, MBTiles, MSSQLSpatial, MVT, MapInfo_File,
           MapML, Memory, MySQL, NGW, ODS,  OGR_GMT,  OpenFileGDB,  PCIDSK,  PDF,  PDS4,  PGDUMP,
           PostgreSQL, S57, SQLite, Selafin, VDV, VICAR, WAsP, XLSX, netCDF
           Default: ESRI_Shapefile

       options=string[,string,...]
           Creation options
           Examples:
                   ’SHPT=POINTZ’: create 3D point Shapefile data
                   ’GEOM_TYPE=geography’: use geography PostGIS data
                   ’SCHEMA=grass’: create new PostGIS tables in ’grass’ schema

       loadsettings=name
           Name of input file to read settings from

       savesettings=name
           Name for output file where to save current settings

DESCRIPTION

       v.external.out  instructs  GRASS  to  write vector maps in external data format (e.g. ESRI
       Shapefile, Mapinfo, and others) using OGR library. PostGIS data can  be  also  written  by
       built-in GRASS-PostGIS data provider.

NOTES

       Number  of  available  output  formats  (v.external.out  -f)  depends on OGR installation.
       ’PostgreSQL’ format is presented also when GRASS comes with PostgreSQL support (check  for
       ’--with-postgres’ in g.version -b output).

       To  store geometry and attribute data in PostGIS database (’PostgreSQL’ format) GRASS uses
       built-in GRASS-PostGIS data provider. PostGIS data can be written also by OGR library when
       GRASS_VECTOR_OGR  environmental  variable  is  defined  or  GRASS  is  not  compiled  with
       PostgreSQL support.

       Creation options refer to the output format specified by format option. See  the  list  of
       valid  creation  options  at OGR formats specification page, example for ESRI Shapefile or
       PostgreSQL/PostGIS format (section "Layer Creation Options"). Options are  comma-separated
       pairs       (key=value),       the       options       are      case-insensitive,      eg.
       options="SCHEMA=myschema,FID=cat".

   PostgreSQL/PostGIS Creation Options
       Note that built-in GRASS-PostGIS  data  provider  (format=PostgreSQL)  supports  different
       creation options compared to PostgreSQL/PostGIS driver from OGR library:

           •   SCHEMA=<name>  -  name of schema where to create feature tables. If schema doesn’t
               exists, it’s automatically created when writing PostGIS data.

           •   FID=<column> - name of column which will be used  as  primary  key  (feature  id),
               default: fid

           •   GEOMETRY_NAME=<column> name of column which will be used for storing geometry data
               in feature table, default: geom

           •   SPATIAL_INDEX=YES|NO - enable/disable spatial index on geometry  column,  default:
               YES

           •   PRIMARY_KEY=YES|NO - enable/disable primary key on FID column, default: YES

           •   SRID=<value> - spatial reference identifier, default: not defined

           •   TOPOLOGY=YES|NO - enable/disable native PostGIS topology, default: NO
       Options relevant only to topological output (TOPOLOGY=YES):

           •   TOPOSCHEMA_NAME=<schema name> - name of PostGIS Topology schema (relevant only for
               TOPOLOGY=YES), default: topo_<input>

           •   TOPOGEOM_NAME=<column>  -  name  of  column  which  will  be  used   for   storing
               topogeometry data in feature table, default: topo

           •   TOPO_TOLERANCE=<value> - tolerance for PostGIS Topology schema, see CreateTopology
               function for defails, default: 0

           •   TOPO_GEO_ONLY=YES|NO - store in PostGIS Topology  schema  only  data  relevant  to
               Topo-Geo data model, default: NO

           •   SIMPLE_FEATURE=YES|NO  -  build  simple  features geometry in GEOMETRY_NAME column
               from topogeometry data, default: NO
       Note that topological output requires PostGIS version 2 or later.

EXAMPLES

   ESRI Shapefile
       v.external.out can be used along with v.external to  process  external  geodata  in  GRASS
       while writing out the results directly eg. in ESRI Shapefile format:
       # register Shapefile in GRASS mapset:
       v.external input=/path/to/shapefiles layer=cities
       # define output directory for GRASS calculation results:
       v.external.out output=$HOME/gisoutput
       # do something (here: spatial query), write output directly as Shapefile
       v.select ainput=cities atype=point binput=forests btype=area operator=within output=fcities
       Current settings can be printed using -p or -g flag.
       v.external.out -p
       output: /path/to/home/gisoutput
       format: ESRI Shapefile

   PostGIS (simple features)
       PostGIS  data  can  be  accessed directly using GRASS-PostGIS data provider (GRASS must be
       compiled with PostgreSQL support).
       # register PostGIS table in GRASS mapset:
       v.external output=PG:dbname=gisdb layer=cities
       # define output PostGIS database for GRASS calculation results stored as simple features:
       v.external.out output=PG:dbname=gisdb format=PostgreSQL
       # do some processing...
       Note: If the environment variable  GRASS_VECTOR_OGR  is  defined,  or  GRASS  is  compiled
       without  PostgreSQL  support  then  GRASS  will use PostgreSQL driver from OGR library for
       reading and writing PostGIS data.

   PostGIS Topology
       # define output PostGIS database for GRASS calculation results stored as topological elements:
       v.external.out output=PG:dbname=gisdb format=PostgreSQL options=topology=YES
       # do some processing...
       Note: PostGIS  topological  access  is  supported  only  in  built-in  GRASS-PostGIS  data
       provider.

   GRASS native format
       To restore original settings, ie. use the GRASS native format, type:
       v.external.out -r

   Restore settings
       Current settings can be stored to file by specifying output option.
       # define output PostGIS database for GRASS calculation with
       # results stored as topological elements:
       v.external.out output=PG:dbname=gisdb format=PostgreSQL \
         options=topology=YES savesettings=gisdb_topo.txt
       # ... and do some processing in PostGIS Topology
       Back to native format:
       v.external.out -r
       # do some processing in native format
       Restore previous settings from "gisdb_topo.txt" file by specifying loadsettings option.
       v.external.out loadsettings=gisdb_topo.txt
       # ... and do some processing in PostGIS Topology

REFERENCES

           •   GRASS-OGR data provider

           •   OGR vector library C API documentation

           •   GRASS-PostGIS data provider

           •   libpq - C Library

SEE ALSO

        v.external, v.in.ogr, v.out.ogr, v.out.postgis

       See also GRASS user wiki page for more examples.

AUTHOR

       Martin  Landa, Czech Technical University in Prague, Czech Republic (development supported
       by Fondazione Edmund Mach and Comune di Trento, Italy)

SOURCE CODE

       Available at: v.external.out source code (history)

       Accessed: Tuesday Jun 27 11:14:09 2023

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       © 2003-2023 GRASS Development Team, GRASS GIS 8.3.0 Reference Manual