DESCRIPTION

db.select prints result of selection from database based on SQL statement read from input file or from standard input to standard output.

NOTE

If parameters for database connection are already set with db.connect, they are taken as default values and do not need to be spcified each time. Output will be displayed to stdout or can be directed to a file.

EXAMPLES

echo "select * from roads" | db.select 
or
 cat file.sql | db.select 
or
 db.select input=file.sql

Select all from table roads

db.select -c driver=odbc database=mydb table=roads \
          input=file.sql output=result.csv

Select some string attribute, exclude others:

echo "SELECT * FROM archsites WHERE str1 <> 'No Name'" | db.select

Select some string attribute with ZERO length:

echo "SELECT * FROM archsites WHERE str1 IS NULL" | db.select

Select coordinates from PostGIS table:

echo "SELECT x(geo),y(geo) FROM localizzazione" | db.select

Count number of cases falling into same position:
When multiple observation have the spatial coordinates, they can still be counted (if needed, coordinates can be uploaded to the attribute table by v.to.db: 

 
db.select sql="SELECT long,lat,site_id,department,obs,COUNT(long) as count_cases \
               FROM diseases GROUP BY long,lat"

SEE ALSO

GRASS SQL interface,
db.connect, db.describe, db.drivers, db.droptable, db.execute, db.login, db.tables

AUTHOR

Unknown
Modifications: Radim Blazek, ITC-Irst, Trento, Italy

Last changed: $Date$