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<em>v.db.droprow</em> removes vector object(s) (point, line, area, face etc.)
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from a vector map through attribute selection in the table connected
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to the given vector map. It automatically checks the connection for the specified
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v.db.droprow is a front-end to <em>v.extract</em> (reverse selection)
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to allow easier usage.
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The existing database connection(s) can be verified with <em>v.db.connect</em>.
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Dropping all vector points without elevation attribute (North Carolina data set):<br>
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<div class="code"><pre>
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g.region raster=elevation -p
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v.random output=rand5k_elev n=5000
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v.db.addtable map=rand5k_elev column="elevation double precision"
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v.what.rast vect=rand5k_elev rast=elevation column=elevation
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# verify absence of some elevation attributes ("number of NULL attributes"):
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v.univar rand5k_elev type=point column=elevation
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# Remove all vector points lacking elevation attribute
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v.db.droprow rand5k_elev output=rand5k_elev_filt where="elevation IS NULL"
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v.univar rand5k_elev_filt type=point column=elevation
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<a href="db.droptable.html">db.droptable</a>,
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<a href="db.execute.html">db.execute</a>,
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<a href="v.db.addcolumn.html">v.db.addcolumn</a>,
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<a href="v.db.addtable.html">v.db.addtable</a>,
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<a href="v.db.connect.html">v.db.connect</a>,
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<a href="v.db.dropcolumn.html">v.db.dropcolumn</a>,
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<a href="v.db.droptable.html">v.db.droptable</a>,
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<a href="v.db.select.html">v.db.select</a>,
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<a href="v.db.update.html">v.db.update</a>
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<p><i>Last changed: $Date: 2014-12-19 22:55:37 +0100 (Fri, 19 Dec 2014) $</i>