1v.db.droprow(1)             GRASS GIS User's Manual            v.db.droprow(1)
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NAME

6       v.db.droprow   - Removes a vector feature from a vector map through at‐
7       tribute selection.
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KEYWORDS

10       vector, attribute table, database
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SYNOPSIS

13       v.db.droprow
14       v.db.droprow --help
15       v.db.droprow input=name   [layer=string]   where=sql_query  output=name
16       [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]
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18   Flags:
19       --overwrite
20           Allow output files to overwrite existing files
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22       --help
23           Print usage summary
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25       --verbose
26           Verbose module output
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28       --quiet
29           Quiet module output
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31       --ui
32           Force launching GUI dialog
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34   Parameters:
35       input=name [required]
36           Name of input vector map
37           Or data source for direct OGR access
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39       layer=string
40           Layer number or name
41           Vector  features can have category values in different layers. This
42           number determines which layer to use. When used with direct OGR ac‐
43           cess this is the layer name.
44           Default: 1
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46       where=sql_query [required]
47           WHERE conditions of SQL statement without ’where’ keyword
48           Example: income < 1000 and population >= 10000
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50       output=name [required]
51           Name for output vector map
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DESCRIPTION

54       v.db.droprow  removes  vector  object(s) (point, line, area, face etc.)
55       from a vector map through attribute selection in the table connected to
56       the  given  vector  map. It automatically checks the connection for the
57       specified layer.
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NOTES

60       v.db.droprow is a front-end to v.extract (reverse selection)  to  allow
61       easier usage.  The existing database connection(s) can be verified with
62       v.db.connect.
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EXAMPLES

65       Dropping all vector points without elevation attribute (North  Carolina
66       data set):
67       g.region raster=elevation -p
68       v.random output=rand5k_elev n=5000
69       v.db.addtable map=rand5k_elev column="elevation double precision"
70       v.what.rast vect=rand5k_elev rast=elevation column=elevation
71       # verify absence of some elevation attributes ("number of NULL attributes"):
72       v.univar rand5k_elev type=point column=elevation
73       # Remove all vector points lacking elevation attribute
74       v.db.droprow rand5k_elev output=rand5k_elev_filt where="elevation IS NULL"
75       # verify:
76       v.univar rand5k_elev_filt type=point column=elevation
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SEE ALSO

79        db.droptable, db.execute, v.db.addcolumn, v.db.addtable, v.db.connect,
80       v.db.dropcolumn, v.db.droptable, v.db.select, v.db.update
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82        GRASS SQL interface
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AUTHOR

85       Markus Neteler
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SOURCE CODE

88       Available at: v.db.droprow source code (history)
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90       Accessed: Saturday Jan 21 20:41:02 2023
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92       Main index | Vector index | Topics index | Keywords index  |  Graphical
93       index | Full index
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95       © 2003-2023 GRASS Development Team, GRASS GIS 8.2.1 Reference Manual
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99GRASS 8.2.1                                                    v.db.droprow(1)