Puneet, Something like this? This is a bit old. We have some example in our book using Common Table Expressions (CTEs) in chapter 8. You can download the code to see those as well. http://www.postgis.us/chapter_08
http://www.bostongis.com/postgis_translate.snippet As far as storing two geometry columns in one table. Yes -- Just do it by creating another column that is geometry (or using AddGeometryColumn function). We do it all the time. Leo http://www.postgis.us -----Original Message----- From: postgis-users-boun...@postgis.refractions.net [mailto:postgis-users-boun...@postgis.refractions.net] On Behalf Of Mr. Puneet Kishor Sent: Monday, March 07, 2011 11:13 PM To: PostGIS Users Discussion Subject: [postgis-users] Creating a grid purely in SQL Given a top-left starting point [ulx, uly], and a cell width 'w' and height 'h', is it possible to create a table entirely in SQL populated with rows increasing from left to right up to X and top to bottom up to Y. The table schema would be something like -- CREATE TABLE cells ( cell_id INTEGER NOT NULL, xmid DOUBLE PRECISION, ymid DOUBLE PRECISION, the_geom GEOMETRY, CONSTRAINT cells_pkey PRIMARY KEY (cell_id) ); where xmid = (xmin + xmax) / 2 and ymid = (ymin + ymax) / 2, [xmin, ymin, xmax, ymax] being the corners of each cell. A bonus question -- is it possible to store two geometry columns in one table? For example, if I wanted to store the geometry for both the center points [xmin, ymid] as well as the box [xmin, ymin, xmax, ymax], would that be possible? Would that even be recommended (for example, to speed up queries/drawing, etc.). Puneet. _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
