1db.select(1)                  Grass User's Manual                 db.select(1)
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NAME

6       db.select  - Selects data from attribute table.
7       Performs SQL query statement(s).
8

KEYWORDS

10       database, attribute table, SQL
11

SYNOPSIS

13       db.select
14       db.select --help
15       db.select   [-cdvt]    [sql=sql_query]     [input=name]    [table=name]
16       [driver=name]     [database=name]     [separator=character]     [verti‐
17       cal_separator=character]        [null_value=string]       [output=name]
18       [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]
19
20   Flags:
21       -c
22           Do not include column names in output
23
24       -d
25           Describe query only (don’t run it)
26
27       -v
28           Vertical output (instead of horizontal)
29
30       -t
31           Only test query, do not execute
32
33       --overwrite
34           Allow output files to overwrite existing files
35
36       --help
37           Print usage summary
38
39       --verbose
40           Verbose module output
41
42       --quiet
43           Quiet module output
44
45       --ui
46           Force launching GUI dialog
47
48   Parameters:
49       sql=sql_query
50           SQL SELECT statement
51           Example: select * from towns where population > 10000
52
53       input=name
54           Name of file containing SQL select statement(s)
55           ’-’ for standard input
56
57       table=name
58           Name of table to query
59
60       driver=name
61           Name of database driver
62           Options: dbf, mesql, mysql, odbc, ogr, pg, sqlite
63           Default: sqlite
64
65       database=name
66           Name of database
67           Default: $GISDBASE/$LOCATION_NAME/$MAPSET/sqlite/sqlite.db
68
69       separator=character
70           Field separator
71           Special characters: pipe, comma, space, tab, newline
72           Default: pipe
73
74       vertical_separator=character
75           Vertical record separator (requires -v flag)
76           Special characters: pipe, comma, space, tab, newline
77
78       null_value=string
79           String representing NULL value
80
81       output=name
82           Name for output file (if omitted or "-" output to stdout)
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DESCRIPTION

85       db.select prints result of selection from database based on SQL  state‐
86       ment  read  from  input file or from standard input to standard output.
87       Each individual query has to be written on one single line and  differ‐
88       ent queries have to be written on separate lines.
89

NOTE

91       If  parameters for database connection are already set with db.connect,
92       they are taken as default values and do not need to be  specified  each
93       time. Output will be displayed to standard output or can be directed to
94       a file (option output).
95

EXAMPLES

97   Basic usage
98       db.select sql="select * from roads"
99       or
100       echo "select * from roads" | db.select input=-
101       or
102       db.select input=file.sql
103       or
104       cat file.sql | db.select input=-
105
106       Select all from table roads:
107       db.select -c driver=odbc database=mydb table=hospitals \
108                 input=file.sql output=result.csv
109
110       Select some string attribute, exclude others:
111       db.select sql="SELECT * FROM archsites WHERE str1 <> ’No Name’"
112
113       Select some string attribute with ZERO length:
114       db.select sql="SELECT * FROM archsites WHERE str1 IS NULL"
115
116       Select coordinates from PostGIS table:
117       db.select sql="SELECT x(geo),y(geo) FROM localizzazione"
118
119   Execute multiple SQL statements
120       cat file.sql
121       SELECT * FROM busstopsall WHERE cat = 1
122       SELECT cat FROM busstopsall WHERE cat > 4 AND cat < 8
123       db.select input=file.sql
124
125   Count number of cases falling into same position
126       When multiple observation have the spatial coordinates, they can  still
127       be counted (if needed, coordinates can be uploaded to the attribute ta‐
128       ble by v.to.db:
129       db.select sql="SELECT long,lat,site_id,department,obs,COUNT(long) as count_cases \
130                      FROM diseases GROUP BY long,lat"
131

SEE ALSO

133         db.connect,  db.describe,   db.drivers,   db.droptable,   db.execute,
134       db.login, db.tables
135
136        GRASS SQL interface
137

AUTHORS

139       Original author unknown (probably CERL)
140       Modifications by Radim Blazek, ITC-Irst, Trento, Italy
141       Support  for  multiple statements by Martin Landa, Czech Technical Uni‐
142       versity in Prague
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SOURCE CODE

145       Available at: db.select source code (history)
146
147       Main index | Database index | Topics index | Keywords index | Graphical
148       index | Full index
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150       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual
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154GRASS 7.8.2                                                       db.select(1)
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