Vector modules changing db should call Vect_set_db_updated

[rblazek]

All vector modules which modify its attribute table (structure or data) should call Vect_set_db_updated like v.what.rast for example does.

It involves most v.db.* modules.

[neteler]

Please indicate the names of the modules or a function to search for in order to identify these modules.

[neteler]

The original QGIS bug (​http://trac.osgeo.org/qgis/ticket/1631) mentions v.db.addcol which is a script. Hence, Vect_set_db_updated() cannot be called. It appears that the function calls Vect_write_dblinks(Map) which modifies the dbln file (​http://download.osgeo.org/grass/grass6_progman/field_8c_source.html#l00690).

Question: would a "touch /path/to/vector/mapname/dbln" be sufficient to indicate the dbln file as updated?

[rblazek]

Yes, touch would work but:

• Is it portable? I think that it is always better to avoid UNIX specific commands even if it is already requirement.

• It is maybe better to keep functionality in one place. An option can be added to v.db.connect, Vect_set_db_updated() called form v.db.connect and v.db.connect called from scripts.

[neteler]

This is still an issue in ​http://trac.osgeo.org/qgis/ticket/1631

[mlennert]

See attached patch for an implementation of Radim's suggestion of adding a flag to v.db.connect which call Vect_set_db_updated(). Scripts that change the attibute file could then call 'v.db.connect -u map=' to signal the update of the attribute file.

The diff is against dev6, but should be easily applicable in the other branches.

Moritz