v.db.reconnect.all - GRASS GIS manual

NAME

v.db.reconnect.all - Reconnects attribute tables for all vector maps from the current mapset to a new database.

KEYWORDS

SYNOPSIS

v.db.reconnect.all

v.db.reconnect.all --help

v.db.reconnect.all [-cd] [old_database=name] [old_schema=name] [new_driver=string] [new_database=name] [new_schema=name] [--help] [--verbose] [--quiet] [--ui]

Flags:

-c: Copy attribute tables to the target database if not exist
-d: Delete attribute tables from the source database
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

old_database=name: Name of source database
old_schema=name: Name of source database schema; Do not use this option if schemas are not supported by driver/database server
new_driver=string: Name for target driver
new_database=name: Name for target database
new_schema=name: Name for target database schema; Do not use this option if schemas are not supported by driver/database server

DESCRIPTION
NOTES
EXAMPLES
SEE ALSO
AUTHORS

DESCRIPTION

v.db.reconnect.all changes database connection of all layers of all vector maps in the current mapset from the source (old_database) to the target (new_database) database. If a link does not match the old_database it is left untouched.

If no new database is given, the default datase of the mapset is used as printed by db.connect -g. If no old database is given, all layers without a link in the new database will be liniked to the new database. If an old database is given, only links in the old database will be changed.

Optionally attribute tables in new_database can be created if not exist by -c flag. In this case v.db.reconnect.all also tries to create an index on key column (usually "cat" column).

NOTES

The value of the old_database option needs to be the exact string which appears as the fourth field printed by v.db.connect -g.

v.db.connect -g map=census 
1/census|census|cat|/home/user/grassdata/nc_spm_base/PERMANENT/dbf/|dbf

v.db.reconnect.all respect also variables to be substituted. In the example above, database /home/user/grassdata/nc_spm_base/PERMANENT/dbf/ can be also defined as '$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/' (see examples).

Attribute tables from old_database are after reconnecting left untouched. v.db.reconnect.all deletes those tables automatically only when -d flag is given.

Also note that v.db.reconnect.all doesn't change default database driver or database (db.connect -p). Default database connection settings for newly created attribute data can be defined by db.connect.

EXAMPLES

In the examples below are assumed, that attribute tables are linked to the vector maps through DBF database driver.

Reconnect DBF attribute tables to SQLite database

Reconnect DBF attribute tables linked to the vector maps in the current mapset to SQLite database:

v.db.reconnect.all old_database='$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/' \
 new_driver=sqlite new_database='$GISDBASE/$LOCATION_NAME/$MAPSET/sqlite/sqlite.db'

If attribute table doesn't exist in the target database (new_database) then the module prints an error message.

Convert DBF attribute tables to SQLite database

For coping DBF tables to SQLite database and reconnecting them for all vector maps in the current mapset must be defined also -c flag.

v.db.reconnect.all -c old_database='$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/' \
 new_driver=sqlite new_database='$GISDBASE/$LOCATION_NAME/$MAPSET/sqlite/sqlite.db'

or alternatively

# set default connection (sqlite)
db.connect -d
# verify default connection
db.connect -g
# reconnect
v.db.reconnect.all -c old_database='$GISDBASE/$LOCATION_NAME/$MAPSET/dbf/'

To automatically remove original DBF attribute tables after reconnecting the vector maps use -d flag. Note that attribute tables will be deleted permanently from the source database. This option should be used very carefully!

Convert GRASS 6 vector map to GRASS 7 including attribute transfer from DBF to SQLite

To become usable in GRASS 7, all vector maps in a mapset need to be updated:

# first rebuild topology for all vector maps
v.build.all

# set new default db connection (to SQLite default)
db.connect -d

# copy attribute tables from old DB to new SQLite DB, delete old tables in DBF format
v.db.reconnect.all -cd

AUTHORS

Radim Blazek
Major update by Martin Landa, Czech Technical University in Prague, Czech Republic

SOURCE CODE

Available at: v.db.reconnect.all source code (history)

Accessed: Sunday Jan 22 07:37:44 2023