DESCRIPTION
v.db.addtable creates and adds a new attribute table to a given vector
map. It links the table to the specified layer of the vector map. If the vector
map is not yet linked to any table, new a database link is established based on
the MAPSET database settings (see db.connect).
NOTES
v.db.addtable is a front-end to db.execute to allow easier
usage.
v.db.addtable will only insert category values into the table for those features
which actually have a category value in the relevant layer. The use can add
category values automatically by using v.category or manually with
wxGUI vector digitizer
before running v.db.addtable. Or one can run v.db.addtable first
and then use either a combinatino of v.category + v.to.db or
wxGUI vector digitizer
to add the relevant lines to the table.
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.
EXAMPLE
Adding a new attribute table with a single column to default layer 1:
g.copy vect=roadsmajor,myroads
v.db.addtable myroads columns="slope double precision"
v.db.connect -p myroads
v.info -c myroads
Adding a new attribute table with two columns to layer 2:
g.copy vect=roadsmajor,myroads
v.db.addtable myroads columns="slope double precision, roadname varchar(15)" layer=2
v.db.connect -p myroads
v.info -c myroads
v.info -c myroads layer=2
SEE ALSO
db.connect,
db.droptable,
db.execute,
v.db.addtable,
v.db.connect,
v.db.dropcol,
v.db.droptable,
v.db.select,
v.db.update
GRASS SQL interface
AUTHOR
Markus Neteler
Last changed: $Date$