1db.execute(1) GRASS GIS User's Manual db.execute(1)
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6 db.execute - Executes any SQL statement.
7 For SELECT statements use ’db.select’.
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10 database, attribute table, SQL
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13 db.execute
14 db.execute --help
15 db.execute [-i] [sql=sql_query] [input=name] [driver=name]
16 [database=name] [schema=name] [--help] [--verbose] [--quiet]
17 [--ui]
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19 Flags:
20 -i
21 Ignore SQL errors and continue
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23 --help
24 Print usage summary
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26 --verbose
27 Verbose module output
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29 --quiet
30 Quiet module output
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32 --ui
33 Force launching GUI dialog
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35 Parameters:
36 sql=sql_query
37 SQL statement
38 Example: update rybniky set kapri = ’hodne’ where kapri = ’malo’
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40 input=name
41 Name of file containing SQL statement(s)
42 ’-’ for standard input
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44 driver=name
45 Name of database driver
46 Options: dbf, mesql, mysql, odbc, ogr, pg, sqlite
47 Default: sqlite
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49 database=name
50 Name of database
51 Default: $GISDBASE/$LOCATION_NAME/$MAPSET/sqlite/sqlite.db
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53 schema=name
54 Database schema
55 Do not use this option if schemas are not supported by driver/data‐
56 base server
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59 db.execute allows the user to execute SQL statements.
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62 db.execute only executes SQL statements and does not return any data.
63 If you need data returned from the database, use db.select.
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65 If parameters for database connection are already set with db.connect,
66 they are taken as default values and do not need to be specified each
67 time.
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69 If you have a large number of SQL commands to process, it is much much
70 faster to place all the SQL statements into a text file and use input
71 file parameter than it is to process each statement individually in a
72 loop. If multiple instruction lines are given, each SQL line must end
73 with a semicolon.
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75 Please see the individual GRASS SQL interface for how to create a new
76 database.
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79 Create a new table with columns ’cat’ and ’soiltype’:
80 db.execute sql="CREATE TABLE soils (cat integer, soiltype varchar(10))"
81 Create a new table using a file with SQL statements
82 db.execute driver=odbc database=grassdb input=file.sql
83 Insert new row into attribute table:
84 db.execute sql="INSERT INTO mysites (id,name,east,north) values (30,’Ala’,1657340,5072301)"
85 Update attribute entries to new value based on SQL rule:
86 db.execute sql="UPDATE roads SET travelcost=5 WHERE cat=1"
87 Update attribute entries to new value based on SQL rule:
88 db.execute sql="UPDATE dourokukan SET testc=50 WHERE testc is NULL"
89 Delete selected rows from attribute table:
90 db.execute sql="DELETE FROM gsod_stationlist WHERE latitude < -91"
91 Add new column to attribute table:
92 db.execute sql="ALTER TABLE roads ADD COLUMN length double"
93 Column type conversion - update new column from existing column (all
94 drivers except for DBF):
95 # ’z_value’ is varchar and ’z’ is double precision:
96 echo "UPDATE geodetic_pts SET z = CAST(z_value AS numeric)" | db.execute input=-
97 Drop column from attribute table:
98 db.execute sql="ALTER TABLE roads DROP COLUMN length"
99 Drop table (not supported by all drivers):
100 db.execute sql="DROP TABLE fmacopy"
101 Update attribute with multiple SQL instructions in file (e.g.,
102 file.sql, instruction line must end with a semicolon):
103 UPDATE roads SET travelcost=5 WHERE cat=1;
104 UPDATE roads SET travelcost=2 WHERE cat=2;
105 db.execute input=file.sql
106 Join table ’myroads’ to table ’extratab’ based on common ’cat’ column
107 values (not supported by DBF driver):
108 db.execute sql="UPDATE extratab SET names=(SELECT label FROM myroads WHERE extratab.cat=myroads.cat)"
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111 db.columns, db.describe, db.drivers, db.droptable, db.login, db.se‐
112 lect, db.tables,
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114 GRASS SQL interface
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117 CERL
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120 Available at: db.execute source code (history)
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122 Accessed: Saturday Jan 21 21:14:04 2023
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124 Main index | Database index | Topics index | Keywords index | Graphical
125 index | Full index
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127 © 2003-2023 GRASS Development Team, GRASS GIS 8.2.1 Reference Manual
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131GRASS 8.2.1 db.execute(1)