UM Geospatial Digital Special Collections

Citation: Department of Commerce, U.S. Census Bureau, Geography Division, Spatial Data Collection and Products Branch (2021). 2021 Florida Census Block Groups - Florida [gis dataset]. Department of Commerce. https://www.census.gov/geographies/mapping-files/time-series/geo/tiger-line-file.html. last updated: 2024-05-01 (update frequency: Never). Abstract: The Census Block Groups data provides a stable set of geographic units for the presentation of census data and comparison back to previous decennial censuses. Key words: Florida, Census, 2021, Tract, Census Block Group, Geography Open Geospatial Consortium Standards: vector tiles | WMS (coming soon) | WFS (coming soon) ETL documentation

ETL for fl_2021_tl_bg

######### # GDSC ETL is performed in two steps: shell script to ETL data into postgres # and then additional transformations with SQL in postGIS (if needed). #### ######### # Step 1 - bash script (pseudo code) #### # create directory structure and move into it mkdir -p /data/fl_2021_tl_bg/{download,etl} && cd /data/fl_2021_tl_bg # set update flag based on last update and update frequency do_update=0 if date() < last_update + update_frequency else do_update = 1 # download if update flag is set: if do_update == 1 then wget -O download/fl_2021_tl_bg.zip 'https://www2.census.gov/geo/tiger/TIGER2021/BG/tl_2021_12_bg.zip' # unzip to download directory if update flag is set if do_update == 1 then unzip -d download download/fl_2021_tl_bg.zip && rm download/fl_2021_tl_bg.zip # load into postGIS with: ogr2ogr -lco GEOMETRY_NAME=geom -f PostgreSQL PG:"" download/tl_2021_12_bg.shp -nlt multipolygon -nln fl_2021_tl_bg ######### # Step 2 - SQL script (pseudo code): #### # remove duplicate points and make geometries valid: UPDATE fl_2021_tl_bg SET geom=ST_MakeValid(ST_RemoveRepeatedPoints(geom));" # add local geometry column and reproject existing geometries into local EPSG: SELECT AddGeometryColumn ( 'fl_2021_tl_bg', 'geom_local',2236,'multipolygon',2 ); UPDATE fl_2021_tl_bg SET geom_local=ST_Transform(ST_Multi(geom),2236); CREATE INDEX fl_2021_tl_bg_geom_local_idx ON fl_2021_tl_bg USING GIST (geom_local); NOTIFY pgrst, 'reload schema';"