another example of ST_Union

git-svn-id: http://svn.osgeo.org/postgis/trunk@8364 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/doc/reference_raster.xml b/doc/reference_raster.xml
index 15f5300d5aabbf522fb226b4088e4f6411c03ee0..736a80dc3520bf5dd14cb5c5d12c3de12da74164 100644 (file)
--- a/doc/reference_raster.xml
+++ b/doc/reference_raster.xml
@@ -6594,12 +6594,21 @@ UPDATE wind
                        </refsection>
                                
                        <refsection>
-                               <title>Examples: Reconstitute a chunked raster tile</title>
+                               <title>Examples: Reconstitute a single band chunked raster tile</title>
                                <programlisting>-- this creates a single band from first band of raster tiles
 -- that form the original file system tile
 SELECT filename, ST_Union(rast) As file_rast
 FROM sometable WHERE filename IN('dem01', 'dem02') GROUP BY filename;</programlisting>
                        </refsection>
+                       
+                       <refsection>
+                               <title>Examples: Reconstitute a single band chunked raster tile</title>
+                               <programlisting>-- this creates a muli band raster collecting all the tiles that intersect a line
+SELECT ST_AddBand(NULL,ARRAY[ST_Union(rast,1), ST_Union(rast,2), ST_Union(rast,3) ])
+FROM aerials.boston
+WHERE ST_Intersects(rast,  ST_GeomFromText('LINESTRING(230486 887771, 230500 88772)',26986) );</programlisting>
+                       </refsection>
+                       
                
                        <!-- Optionally add a "See Also" section -->
                        <refsection>