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@@ -1,30 +1,13 @@
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-<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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-<html>
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-<head>
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-<title>SQL support in GRASS GIS</title>
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-<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
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-<link rel="stylesheet" href="grassdocs.css" type="text/css">
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-</head>
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+<!-- meta page description: SQL support in GRASS GIS -->
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-<!-- This file is lib/db/sqlp/description.html -->
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-
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-<body bgcolor="white">
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-
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-<img src="grass_logo.png" alt="GRASS logo"><hr align=center size=6 noshade>
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-
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-<!-- meta page description: SQL support introduction -->
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-<h2>SQL support in GRASS GIS</h2>
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-
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-GRASS can use various RDBMS and embedded databases.
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-SQL queries are directly passed to the underlying
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-database system.
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-The set of supported SQL commands depends on the RDMBS
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-and driver selected.
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+GRASS can use various RDBMS and embedded databases. SQL queries are
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+directly passed to the underlying database system. The set of
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+supported SQL commands depends on the RDMBS and driver selected.
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<h2>Drivers</h2>
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-The list of available drivers can vary in various binary
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-distributions of GRASS.
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-<p>
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+
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+The list of available drivers can vary in various binary distributions
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+of GRASS.
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<table border=1 >
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<tr><td><a href="grass-dbf.html">dbf</a></td><td>DBF files. Data are stored in DBF files.</td>
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@@ -69,27 +52,34 @@ d.vect map where="individual='juvenile' and area='beach'"
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<h2>EXAMPLES</h2>
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-Display all vector points except for LAMAR valley and <i>extensive trapping</i> (brackets are superfluous in this example):
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+Display all vector points except for LAMAR valley and <i>extensive
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+trapping</i> (brackets are superfluous in this example):
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+
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<div class="code"><pre>
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d.vect trapping_sites_points fcol=black icon=basic/diamond col=white size=13 \
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where="valley <> 'LAMAR' OR (valley = 'LAMAR' AND description = 'extensive trapping')"
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</pre></div>
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<p>
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-Select all attributes from table where str1 column values are not 'No Name':
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+Select all attributes from table where str1 column values are not 'No
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+Name':
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+
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<div class="code"><pre>
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echo "SELECT * FROM archsites WHERE str1 <> 'No Name'" | db.select
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</pre></div>
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<p>
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-<p><b>Example</b> of subquery expressions from a list (does not work for DBF driver):
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+<p><b>Example</b> of subquery expressions from a list (does not work
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+for DBF driver):
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+
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<div class="code"><pre>
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v.db.select mysites where="id IN ('P04', 'P05')"
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</pre></div>
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<p><b>Example</b> of pattern matching:
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+
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<div class="code"><pre>
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# field contains string:
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@@ -106,6 +96,7 @@ v.db.select mysites where="id LIKE 'P%'"
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</pre></div>
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<p><b>Example</b> of null handling:
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+
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<div class="code"><pre>
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v.db.addcolumn map=roads col="nulltest int"
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v.db.update map=roads col=nulltest value=1 where="cat > 2"
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@@ -114,7 +105,9 @@ v.db.update map=roads col=nulltest value=2 where="cat <= 2"
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</pre></div>
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-<p><b>Examples</b> of complex expressions in updates (using v.db.* modules):
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+<p><b>Examples</b> of complex expressions in updates (using v.db.*
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+modules):
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+
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<div class="code"><pre>
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v.db.addcolumn map=roads col="exprtest double precision"
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v.db.update map=roads col=exprtest value=cat/nulltest
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@@ -122,7 +115,9 @@ v.db.update map=roads col=exprtest value=cat/nulltest+cat where=cat=1
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</pre></div>
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-<p><b>Examples</b> of complex expressions in updates (using db.* modules):
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+<p><b>Examples</b> of complex expressions in updates (using db.*
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+modules):
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+
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<div class="code"><pre>
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echo "UPDATE roads SET exprtest=null"
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echo "UPDATE roads SET exprtest=cat/2" | db.execute
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@@ -133,15 +128,18 @@ echo "UPDATE roads SET exprtest=cat/3*(cat+1) WHERE exprtest IS NULL" | db.execu
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<p>
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-Instead of creating and updating new columns with an expression,
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-you can use the expression directly in a command:
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+Instead of creating and updating new columns with an expression, you
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+can use the expression directly in a command:
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+
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<div class="code"><pre>
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d.vect roads where="(cat/3*(cat+1))>8"
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d.vect roads where="cat>exprtest"
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</pre></div>
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-<p><b>Example</b> of changing a SQL type (type casting, does not work for DBF driver):
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+<p><b>Example</b> of changing a SQL type (type casting, does not work
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+for DBF driver):
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+
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<div class="code"><pre>
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# North Carolina data set: convert string column to double precision
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# copy map into current mapset
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@@ -154,7 +152,9 @@ v.db.update mygeodetic_pts col=zval \
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where="z_value <> 'N/A'"
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</pre></div>
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-<p><b>Example</b> of concatenating fields (does not work for DBF driver):
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+<p><b>Example</b> of concatenating fields (does not work for DBF
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+driver):
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+
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<div class="code"><pre>
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v.db.update vectormap column=column3 qcolumn="column1 || column2"
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</pre></div>
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@@ -171,11 +171,3 @@ v.db.update vectormap column=column3 qcolumn="column1 || column2"
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<p>
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<i>Last changed: $Date$</i>
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-<hr>
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-<br>
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-<a href="index.html">Main index</a> -
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-<a href="database.html">database index</a> -
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-<a href="full_index.html">full index</a>
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-<p>© 2008-2012 <a href="http://grass.osgeo.org">GRASS Development Team</a>
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-</body>
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-</html>
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Martin Landa