db.select(1grass) | GRASS GIS User's Manual | db.select(1grass) |
db.select - Selects data from attribute table.
Performs SQL query statement(s).
database, attribute table, SQL
db.select
db.select --help
db.select [-cdvt] [sql=sql_query]
[input=name] [table=name]
[driver=name] [database=name]
[separator=character]
[vertical_separator=character]
[null_value=string] [output=name]
[--overwrite] [--help] [--verbose] [--quiet]
[--ui]
db.select prints result of selection from database based on SQL statement read from input file or from standard input to standard output. Each individual query has to be written on one single line and different queries have to be written on separate lines.
If parameters for database connection are already set with db.connect, they are taken as default values and do not need to be specified each time. Output will be displayed to standard output or can be directed to a file (option output).
db.select sql="select * from roads"
or
echo "select * from roads" | db.select input=-
or
db.select input=file.sql
or
cat file.sql | db.select input=-
Select all from table roads:
db.select -c driver=odbc database=mydb table=hospitals \ input=file.sql output=result.csv
Select some string attribute, exclude others:
db.select sql="SELECT * FROM archsites WHERE str1 <> ’No Name’"
Select some string attribute with ZERO length:
db.select sql="SELECT * FROM archsites WHERE str1 IS NULL"
Select coordinates from PostGIS table:
db.select sql="SELECT x(geo),y(geo) FROM localizzazione"
cat file.sql SELECT * FROM busstopsall WHERE cat = 1 SELECT cat FROM busstopsall WHERE cat > 4 AND cat < 8 db.select input=file.sql
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"
db.connect, db.describe, db.drivers, db.droptable, db.execute, db.login, db.tables
GRASS SQL interface
Original author unknown (probably CERL)
Modifications by Radim Blazek, ITC-Irst, Trento, Italy
Support for multiple statements by Martin Landa, Czech Technical University in
Prague
Available at: db.select source code (history)
Accessed: Monday Apr 01 03:07:09 2024
Main index | Database index | Topics index | Keywords index | Graphical index | Full index
© 2003-2024 GRASS Development Team, GRASS GIS 8.3.2 Reference Manual
GRASS 8.3.2 |