db.select1grass
Selects data from attribute table. performs sql query statement(s).
Usage
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]
Keywords
database, attribute table, SQL
Overview
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.
Note
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).
Examples
Basic usage
db.select sql="select * from roads"or
echo "select * from roads" | db.select input=-or
db.select input=file.sqlor
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"Execute multiple SQL statements
cat file.sqlSELECT * FROM busstopsall WHERE cat = 1SELECT cat FROM busstopsall WHERE cat > 4 AND cat < 8db.select input=file.sql
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"
Source code
Available at: db.select source code (history)
Accessed: Monday Feb 24 17:50:23 2025
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Releases
10 releases since Debian 4.0 (Etch); the text changed 9 times.