.vAttachDatabase

<code>.vAttachDatabase()</code> adds a table to a GRASS vector. This table is meant to be "invisible" to most users--they should use interact with attribute tables using the <code>GVector</code> slot <code>@table</code>. Some functions require tables (e.g., <code>extract()</code> and <code>spatSample()</code>). This function is mostly of use to developers.

internal

Processing of large-in-memory/large-on disk rasters and spatial
vectors using 'GRASS GIS' <https://grass.osgeo.org/>. Most functions in
the 'terra' package are	recreated. Processing of medium-sized and smaller
spatial objects will nearly always be faster using 'terra' or 'sf', but
for large-in-memory/large-on-disk objects, 'fasterRaster' may be faster.
To use most of the functions, you must have the stand-alone version (not
the 'OSGeoW4' installer version) of 'GRASS GIS' 8.0 or higher.

Adam B. Smith

fasterRaster

Faster Raster and Spatial Vector Processing Using 'GRASS GIS'

.vAttachDatabase function

<dl><dt>x</dt>
<dd>A <code>GVector</code> or the name of a vector in GRASS.</dd>
<dt>table</dt>
<dd>Either <code>NULL</code> (default), or a <code>data.frame</code> or <code>data.table</code>, or a numeric or integer vector:<ul>
<li>If <code>NULL</code>, then a bare minimal table will be created with a column named <code>cat</code>, holding sequential integer values.</li>
<li>If a <code>data.frame</code> or <code>data.table</code> and no column is named <code>cat</code>, one will be created with sequential integer values. If the table does have a column named <code>cat</code>, then it should have integer (not just numeric) values.</li>
<li>If a <code>vector</code>, then these are coerced to type <code>integer</code> and used to define the <code>cat</code> column.</li>
</ul></dd>There should be one row/value per geometry in <code>x</code>.
<dt>replace</dt>
<dd>Logical: If <code>TRUE</code>, replace the existing database connection.</dd>
<dt>cats</dt>
<dd>Either <code>NULL</code> (default), or an integer vector: This is provided as a means to save time by passing <code>cats</code> to this function if it has already been generated by a calling function.</dd></dl>

Arguments

Add a database table to a GRASS attribute table — .vAttachDatabase

<dl>

<dt>x</dt>
<dd>A <code>GVector</code> or the name of a vector in GRASS.</dd>


<dt>table</dt>
<dd>Either <code>NULL</code> (default), or a <code>data.frame</code> or <code>data.table</code>, or a numeric or integer vector:<ul>
<li>If <code>NULL</code>, then a bare minimal table will be created with a column named <code>cat</code>, holding sequential integer values.</li>
<li>If a <code>data.frame</code> or <code>data.table</code> and no column is named <code>cat</code>, one will be created with sequential integer values. If the table does have a column named <code>cat</code>, then it should have integer (not just numeric) values.</li>
<li>If a <code>vector</code>, then these are coerced to type <code>integer</code> and used to define the <code>cat</code> column.</li>
</ul>

There should be one row/value per geometry in <code>x</code>.</dd>


<dt>replace</dt>
<dd>Logical: If <code>TRUE</code>, replace the existing database connection.</dd>


<dt>cats</dt>
<dd>Either <code>NULL</code> (default), or an integer vector: This is provided as a means to save time by passing <code>cats</code> to this function if it has already been generated by a calling function.</dd>

</dl>

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.vAttachDatabase: Add a database table to a GRASS attribute table

Description

Usage

Value

Arguments