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Getting ready

We will be reusing and building upon data used in the Adding PostGIS layers – QGIS recipe. If you skipped over this recipe, you will want to do the following:

Download the following ZIP file from the U.S. Census Bureau's FTP site:

ftp://ftp2.census.gov/geo/tiger/TIGER2012/EDGES/tl_2012_39035_edges.zip

The shapefile is All Lines for Cuyahoga county in Ohio, which consist of roads and streams, among other line features.

Extract the ZIP file to your working directory and then load it into your database using shp2pgsql. Be sure to specify the spatial reference system, which is EPSG: 4269, and name the table lines.

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