NAME

       v.db.select  - Prints vector map attributes.

KEYWORDS

       vector, attribute table, database, SQL

SYNOPSIS

       v.db.select
       v.db.select --help
       v.db.select      [-rcvf]      map=name      [layer=string]       [columns=name[,name,...]]
       [where=sql_query]                   [group=string]                   [separator=character]
       [vertical_separator=character]      [null_value=string]      [file=name]     [--overwrite]
       [--help]  [--verbose]  [--quiet]  [--ui]

   Flags:
       -r
           Print minimal region extent of selected vector features instead of attributes

       -c
           Do not include column names in output

       -v
           Vertical output (instead of horizontal)

       -f
           Exclude attributes not linked to features

       --overwrite
           Allow output files to overwrite existing files

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       map=name [required]
           Name of vector map
           Or data source for direct OGR access

       layer=string
           Layer number or name
           Vector features can have category values in different layers. This  number  determines
           which layer to use. When used with direct OGR access this is the layer name.
           Default: 1

       columns=name[,name,...]
           Name of attribute column(s)

       where=sql_query
           WHERE conditions of SQL statement without ’where’ keyword
           Example: income < 1000 and population >= 10000

       group=string
           GROUP BY conditions of SQL statement without ’group by’ keyword

       separator=character
           Field separator
           Special characters: pipe, comma, space, tab, newline
           Default: pipe

       vertical_separator=character
           Output vertical record separator
           Special characters: pipe, comma, space, tab, newline

       null_value=string
           String representing NULL value

       file=name
           Name for output file (if omitted or "-" output to stdout)

DESCRIPTION

       v.db.select  prints attributes of a vector map from one or several user selected attribute
       table columns.

EXAMPLES

       All examples are based on the North Carolina sample dataset.

   Select and show entire table
       v.db.select map=roadsmajor
       cat|MAJORRDS_|ROAD_NAME|MULTILANE|PROPYEAR|OBJECTID|SHAPE_LEN
       1|1|NC-50|no|0|1|4825.369405
       2|2|NC-50|no|0|2|14392.589058
       3|3|NC-98|no|0|3|3212.981242
       4|4|NC-50|no|0|4|13391.907552
       ...

   Select and show single column from table
       Note: multiple columns can be specified as comma separated list.
       v.db.select map=roadsmajor column=ROAD_NAME
       NC-50
       NC-50
       NC-98
       NC-50
       NC-98
       ...

   Print region extent of selected vector features
       v.db.select -r map=roadsmajor where="ROAD_NAME = ’NC-98’"
       n=248425.389891
       s=245640.640081
       w=635906.517653
       e=661979.801880

   Select empty vector features (no data entries)
       v.db.select geonames_wake where="ALTERNATEN IS NULL"
       cat|GEONAMEID|NAME|ASCIINAME|ALTERNATEN|FEATURECLA|FEATURECOD|...
       8|4498303|West Raleigh|West Raleigh||P|PPL|US||NC|338759|123|...
       14|4459467|Cary|Cary||P|PPL|US||NC|103945|146|152|America/Iqaluit|...
       31|4452808|Apex|Apex||P|PPL|US||NC|30873|167|134|America/Iqaluit|...
       ...

   Select not empty vector features (no data entries)
       v.db.select geonames_wake where="ALTERNATEN IS NOT NULL"
       cat|GEONAMEID|NAME|ASCIINAME|ALTERNATEN|FEATURECLA|FEATURECOD|...
       9|4487042|Raleigh|Raleigh|Raleigh,...
       31299|4487056|Raleigh-Durham Airport|Raleigh-Durham Airport|...
       ...

   Select features with distinct road names
       v.db.select map=roadsmajor columns=ROAD_NAME group=ROAD_NAME
       ROAD_NAME
       I-40
       I-440
       I-540
       NC-231
       NC-39
       NC-42
       ...
       It is also possible to combine with where option
       v.db.select map=roadsmajor columns=ROAD_NAME,MULTILANE group=ROAD_NAME where=’ROAD_NAME is not null’
       ROAD_NAME|MULTILANE
       I-40|yes
       I-440|yes
       I-540|yes
       NC-231|no
       NC-39|no
       NC-42|no
       NC-50|no
       NC-54|no
       NC-55|no
       NC-96|no
       NC-97|no
       NC-98|no
       US-1|
       US-401|no
       US-64|yes
       US-70|yes
       It can also use more columns in group option
       v.db.select map=roadsmajor columns=ROAD_NAME,MULTILANE group=ROAD_NAME,MULTILANE where=’ROAD_NAME is not null’
       ROAD_NAME|MULTILANE
       I-40|yes
       I-440|yes
       I-540|yes
       NC-231|no
       NC-39|no
       NC-42|no
       NC-50|no
       NC-54|no
       NC-55|no
       NC-96|no
       NC-97|no
       NC-98|no
       US-1|
       US-1|yes
       US-401|no
       US-401|yes
       US-64|yes
       US-70|yes

SEE ALSO

        db.select

AUTHORS

       Radim Blazek, ITC-Irst, Trento, Italy
       Minimal region extent added by Martin Landa, FBK-irst (formerly ITC-irst),  Trento,  Italy
       (2008/08)
       Group option added by Luca Delucchi, Fondazione Edmund Mach, Trento, Italy (2015/12)

SOURCE CODE

       Available at: v.db.select source code (history)

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       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual