UM Geospatial Digital Special Collections

Citation: Census (2024). USA 2020 Zip Code Tabulation Areas [gis dataset]. Census. https://www.census.gov/programs-surveys/geography/guidance/geo-areas/zctas.html. last updated: 2024-12-05 (update frequency: As Needed). Abstract: A polygon representation of the US Zip Code Tabulation Areas (ZCTA) boundaries. Key words: USA, Zipcode Open Geospatial Consortium Standards: dynamic vector tiles | | WMS (coming soon) | WFS (coming soon) Analytical Functions: gdsc_get_attributes(tablename=us_2020_zcta,lat=25.718,lng=-80.279,identifier=objectid,attrs=[objectid,PZIPCODEID],normal='') ETL documentation

ETL for us_2020_zcta

######### # 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/us_2020_zcta/{download,etl} && cd /data/us_2020_zcta # 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/us_2020_zcta.zip 'https://www2.census.gov/geo/tiger/TIGER2020/ZCTA520/tl_2020_us_zcta520.zip' # unzip to download directory if update flag is set if do_update == 1 then unzip -d download download/us_2020_zcta.zip && rm download/us_2020_zcta.zip # load into postGIS with: ogr2ogr -lco GEOMETRY_NAME=geom -f PostgreSQL PG:"" download/tl_2020_us_zcta520.shp -nlt multipolygon -nln us_2020_zcta ######### # Step 2 - SQL script (pseudo code): #### # remove duplicate points and make geometries valid: UPDATE us_2020_zcta SET geom=ST_MakeValid(ST_RemoveRepeatedPoints(geom));" # add local geometry column and reproject existing geometries into local EPSG: SELECT AddGeometryColumn ( 'us_2020_zcta', 'geom_local', 4269, 'multipolygon', 2 ); UPDATE us_2020_zcta SET geom_local=ST_MakeValid(ST_RemoveRepeatedPoints(ST_Transform(ST_Multi(geom), 4269))); CREATE INDEX us_2020_zcta_geom_local_idx ON us_2020_zcta USING GIST (geom_local); NOTIFY pgrst, 'reload schema';"