Skip to content

v.db.addcolumn

Adds one or more columns to the attribute table connected to a given vector map.

v.db.addcolumn map=name [layer=string] columns=name type [,name type,...] [--verbose] [--quiet] [--qq] [--ui]

Example:

v.db.addcolumn map=name columns=name type

grass.script.run_command("v.db.addcolumn", map, layer="1", columns, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("v.db.addcolumn", map="name", columns="name type")

Parameters

map=name [required]
    Name of vector map
    Or data source for direct OGR access
layer=string
    Layer number where to add column(s)
    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
columns=name type [,name type,...] [required]
    Name and type of the new column(s) ('name type [,name type, ...]')
    Types depend on database backend, but all support VARCHAR(), INT, DOUBLE PRECISION and DATE. Example: 'label varchar(250), value integer'
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

map : str, required
    Name of vector map
    Or data source for direct OGR access
    Used as: input, vector, name
layer : str, optional
    Layer number where to add column(s)
    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.
    Used as: input, layer
    Default: 1
columns : str | list[str], required
    Name and type of the new column(s) ('name type [,name type, ...]')
    Types depend on database backend, but all support VARCHAR(), INT, DOUBLE PRECISION and DATE. Example: 'label varchar(250), value integer'
    Used as: name type
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

v.db.addcolumn adds one or more column(s) to the attribute table connected to a given vector map. It automatically checks the connection for the specified layer.

NOTES

v.db.addcolumn is a front-end to db.execute to allow easier usage. The supported types of columns depend on the database backend. However, all backends should support VARCHAR, INT, DOUBLE PRECISION and DATE.

The existing database connection(s) can be verified with v.db.connect.

EXAMPLES

Adding a single column:

g.copy vect=roadsmajor,myroads
v.db.addcolumn myroads columns="slope double precision"
v.info -c myroads

Adding two columns:

g.copy vect=roadsmajor,myroads
v.db.addcolumn myroads columns="slope double precision,myname varchar(15)"
v.info -c myroads

SEE ALSO

db.connect, db.execute, v.db.addtable, v.db.connect, v.db.dropcolumn, v.db.droptable, v.db.select, v.db.update

GRASS SQL interface

AUTHOR

Moritz Lennert (mlennert@club.worldonline.be)

SOURCE CODE

Available at: v.db.addcolumn source code (history)
Latest change: Friday Feb 07 19:16:09 2025 in commit a82a39f