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Correct Spelling and Pronunciation

Let's not dwell on this.

Spelling Pronounced Source
PostgreSQL post-GRES-que-ell https://www.postgresql.org/about/press/faq/
PostGIS post jis http://mapbrief.com/2015/10/22/postgis-is-so-successful-that-it-needs-to-change-its-name/

Also commonly used

Spelling Pronounced Source
Postgres post grez my eyes and ears

As for PostGIS, blame the Canadians...

drake


Installation on Our Government-Issued Windows PC Computers

The simplest path, outlined here, is to download PostgreSQL pre-built binaries from EnterpriseDB, then install the compatible PostGIS bundle from OSGeo.

Install PostgreSQL on Our Government-Issued Windows PC Computers

First, check the PostgreSQL and Windows version matrix here.

https://www.postgresql.org/download/windows/

Then follow the link to "Download the Installer" from EnterpriseDB and install. When prompted for the super user password you will want to remember (or securely vault) what you enter.

Paths and info will pop up during the installation. If you are installing a new version without first removing and older version the port number may be different from the PostgreSQL default, 5432.

What Path
Installation Directory C:\Program Files\PostgreSQL\16
Data Directory C:\Program Files\PostgreSQL\16\data
Database Port 5432
Database Superuser postgres

Add the /bin directory (ex C:\Program Files\PostgreSQL\16\bin) of the installation to your PATH variable. If all goes well the psql program should connect to our local default database and postgres user.

Verification using psql.exe from Mingw:

$ export PGSSLMODE=allow
$ export PGPASSWORD=bemydatabae!
$ export PGHOST=localhost
$ export PGPORT=5432
$ psql -U postgres
psql (16.2)
WARNING: Console code page (437) differs from Windows code page (1252)
         8-bit characters might not work correctly. See psql reference
         page "Notes for Windows users" for details.
Type "help" for help.

postgres=# select version();
                          version
------------------------------------------------------------
 PostgreSQL 16.2, compiled by Visual C++ build 1937, 64-bit
(1 row)

postgres=# SHOW data_directory;
           data_directory
-------------------------------------
 C:/Program Files/PostgreSQL/16/data
(1 row)

postgres=# \q

Install PostGIS on Our Government-Issued Windows PC Computers

Download the PostGIS extension matching your PostgreSQL version from the Open Source Geospatial Foundation (osgeo) download page. For example, to select the installer for 64 bit Windows that is compatible with PostgreSQL 16 choose the pg16 directory and download postgis-bundle-pg16x64-setup-3.4.1-1.exe.

After running the installer verify the installation.

postgres=# select * from pg_available_extensions where name = 'postgis';
  name   | default_version | installed_version |                          comment
---------+-----------------+-------------------+------------------------------------------------------------
 postgis | 3.4.1           |                   | PostGIS geometry and geography spatial types and functions
(1 row)

postgres=# \q

psql: Pretty good, if you're in to that sort of thing

"psql is a terminal-based front-end to PostgreSQL."

Anyone with a 'nix-like background will likely find psql more intuitive than Oracle's SQLPlus. Also, anyone who's ever attempted to control the behavior of SQLPlus via some "SPOOL", "SET DEFINE OFF", etc guesses at the top of an SQLPlus script should find psql refreshing.

A simple psql connection to a database as user "gisuser" on database "gisdatabase" hosted locally. Inputs can be externalized via PGXXXXX environmentals which is a good practice.

$ export PGPASSWORD=PostgisIsMyDataBae!
$ psql -h localhost -U gisuser -d gisdatabase
psql (13.4)
WARNING: Console code page (437) differs from Windows code page (1252)
         8-bit characters might not work correctly. See psql reference
         page "Notes for Windows users" for details.
Type "help" for help.

gisdatabase=# \q

A call to a script in a file using -f

$ psql -h localhost -U gisuser -d gisdatabase -f gisscript.sql

Yields a consistent, nicely formatted output that any shell or scripting language can read. Successes print the action. Errors bounce back as as psql:script:linenumber: info

BEGIN
UPDATE 312
COMMIT
GRANT
CREATE VIEW
GRANT
BEGIN
psql:gisscript.sql:83: ERROR:  Geometry type (Polygon) does not match column type (MultiPolygon)

Select with -t, -A, -F -c

t: tuples only (no column names, footers)

A: unaligned output

F: Field separator

c: command

$ psql -tA -F\| -h localhost -U gisuser -d gisdatabase -c 'select table_schema, table_catalog, table_name from information_schema.tables;'
public|dtm|geography_columns
public|dtm|geometry_columns
public|dtm|spatial_ref_sys
public|dtm|boundary
public|dtm|raster_columns
public|dtm|raster_overviews
public|dtm|sub_label
public|dtm|reuc_lots
public|dtm|condo_units
-- More  --

Servers - Roles and Databases. Databases - Schemas. Life - Infinite possibilities

We create databases on a server. A collection of databases managed by a single PostgreSQL server instance is a database cluster. A database is the top-level container for database objects.

We also create users (or groups of users, aka roles) on a server. With appropriate grants a user may access multiple databases on the same server. But a client connection may only access one database for a given connection.

We create schemas on a database as logical structures. Schemas aren't necessarily assigned to users. By default there's a public schema on each database.

Here's a wild and crazy mix of users, databases, and grants on the Aurora host we had access to during the Pivotal proof of concept. Notice that all privileges for the basemapread user have been revoked except for access to the basemap database.

wild

Moving Oracle stuff over without much private sector thinking seems to pop out one PostgreSQL database with one default public schema for each Oracle schema.

How would you, yes you, organize this?

gritty


EZ loading spatial data using PostGIS shapefile loader, shp2pgsql, and ogr2ogr

PostGIS Shapefile Loader

Comes with the PostGIS bundle install. It's a good place to start.

shapeloaderwin

shapeloader

shp2pgsql

The PostGIS Shapefile Loader GUI described above is a wrapper to shp2pgsql. From the shp2pgsql command line we have many nice flags and options.

https://postgis.net/docs/using_postgis_dbmanagement.html#shp2pgsql_usage

I am partial to converting shapefiles into SQL and plunking the SQL into version control.

For example, given a shapefile of tax blocks, convert the entire thing to PostGIS compatible SQL.

-s: spatial reference identifier

-g: geometry column name

-m: mapping file for column names that were lopped off in the shapefile

-a: append (inserts only)

shp2pgsql -s 2263 -g shape -m /c/matt_projects/dtm2cloud/src/helper/mappingfiles/tax_block_polygon -a /d/matt_projects_data/dtm2cloud/tax_block_polygon.shp tax_block_polygon > /d/matt_projects_data/dtm2cloud/tax_block_polygon.sql

Creates an sql file with many inserts, here's one:

INSERT INTO "tax_block_polygon" ("boro","block","eop_overlap_flag","jagged_st_flag","created_by","created_date","last_modified_by","last_modified_date","section_number","volume_number",shape) VALUES ('3','2386','0','0',NULL,NULL,'LTP',NULL,'8','5','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');

ogr2ogr

Works great if you're into this sort of thing, or must convert directly to/from formats that aren't shapefiles.

For example, load a geojson file to a new table named zone_geo_test.

$ ogr2ogr -f "PostgreSQL" PG:"dbname='gisdatabase' host='localhost' port='5432' user='gisuser' password='y'" "C:\Temp\zone_sdo_dmp.geojson" -nln zone_geo_test

OGR Foreign Data Wrapper

ogr_fdw

Given a PostgreSQL database with access to an ogr-compatible file or database, enable the ogr-fdw extension and treat the file or non-PostgreSQL database like a PostgreSQL table.

https://wiki.postgresql.org/wiki/Foreign_data_wrappers

https://github.com/pramsey/pgsql-ogr-fdw

mschell@T2UA64237XN MINGW64 ~
$ ogr_fdw_info -s /c/Temp -l centerline_2263_2
CREATE SERVER myserver
  FOREIGN DATA WRAPPER ogr_fdw
  OPTIONS (
        datasource 'C:/Temp',
        format 'ESRI Shapefile' );

CREATE FOREIGN TABLE centerline_2263_2 (
  fid bigint,
  geom Geometry(LineString,4269),
  pre_direct varchar,
  l_zip varchar,
  post_type varchar,
  date_creat date,
  time_creat varchar,
  pre_type varchar,
  l_blkfc_id real,
  rw_type real,
  frm_lvl_co real,
  shape_leng real,
  l_high_hn varchar,
  status varchar,
  bike_trafd varchar,
  full_stree varchar,
  l_low_hn varchar,
  r_high_hn varchar,
  snow_pri varchar,
  st_name varchar,
  st_label varchar,
  to_lvl_co real,
  post_modif varchar,
  bike_lane varchar,
  trafdir varchar,
  r_zip varchar,
  r_blkfc_id real,
  date_modif date,
  time_modif varchar,
  physicalid real,
  borocode varchar,
  pre_modifi varchar,
  r_low_hn varchar,
  st_width real,
  post_direc varchar
) SERVER myserver
OPTIONS (layer 'centerline_2263_2');

This SQL is fetching from the shapefile. There is no table named cetnerline_2263_2.

ogr_fdw_action


PL/pgSQL

PL/pgSQL is the most commonly used procedural programming language supported by PostgreSQL. It will look familiar to programmers of other databases. $$ are "dollar quotes" to avoid escaping single quotes within the text. We must specify the language because PostgreSQL also supports pl/perl, pl/python, and some others not part of the core distribution.

CREATE OR REPLACE FUNCTION dummy()
RETURNS VARCHAR AS $$
BEGIN
    RETURN 'X';
END;
$$ LANGUAGE plpgsql;
gisdatabase=# select * from dummy();
 dummy
-------
 X
(1 row)

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