 
NAME
v.db.droprow  - Removes a vector feature from a vector map through attribute selection.
KEYWORDS
vector, 
attribute table, 
database
SYNOPSIS
v.db.droprow
v.db.droprow --help
v.db.droprow input=name  [layer=string]  where=sql_query output=name  [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui] 
Flags:
- --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:
- input=name [required]
- Name of input 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
- where=sql_query [required]
- WHERE conditions of SQL statement without 'where' keyword
- Example: income < 1000 and population >= 10000
- output=name [required]
- Name for output vector map
 
v.db.droprow removes vector object(s) (point, line, area, face etc.)
from a vector map through attribute selection in the table connected
to the given vector map. It automatically checks the connection for the specified
layer.
v.db.droprow is a front-end to 
v.extract (reverse selection)
to allow easier usage.
The existing database connection(s) can be verified with 
v.db.connect.
Dropping all vector points without elevation attribute (North Carolina data set):
g.region raster=elevation -p
v.random output=rand5k_elev n=5000
v.db.addtable map=rand5k_elev column="elevation double precision"
v.what.rast vect=rand5k_elev rast=elevation column=elevation
# verify absence of some elevation attributes ("number of NULL attributes"):
v.univar rand5k_elev type=point column=elevation
# Remove all vector points lacking elevation attribute
v.db.droprow rand5k_elev output=rand5k_elev_filt where="elevation IS NULL"
# verify:
v.univar rand5k_elev_filt type=point column=elevation
GRASS SQL interface
Markus Neteler
SOURCE CODE
  Available at:
  v.db.droprow source code
  (history)
  Latest change: Thursday Jan 26 14:10:26 2023 in commit: cdd84c130cea04b204479e2efdc75c742efc4843
Main index |
Vector index |
Topics index |
Keywords index |
Graphical index |
Full index
© 2003-2025
GRASS Development Team,
GRASS GIS 8.4.1 Reference Manual