v.db.droprow(1grass) GRASS GIS User's Manual v.db.droprow(1grass)
NAME
v.db.droprow - Removes a vector feature from a vector map through at-
tribute 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 ac-
cess 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
DESCRIPTION
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.
NOTES
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.
EXAMPLES
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
SEE ALSO
db.droptable, db.execute, v.db.addcolumn, v.db.addtable, v.db.connect,
v.db.dropcolumn, v.db.droptable, v.db.select, v.db.update
AUTHOR
Markus Neteler
SOURCE CODE
Available at: v.db.droprow source code (history)
Accessed: unknown
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GRASS 7.8.7 v.db.droprow(1grass)
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