102 lines
2.7 KiB
Plaintext
102 lines
2.7 KiB
Plaintext
---------------------------------------------------------------------------
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-- Practical SQL: A Beginner's Guide to Storytelling with Data, 2nd Edition
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-- by Anthony DeBarros
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-- Chapter 18 Code Examples
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----------------------------------------------------------------------------
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-- Connecting psql to a database on a local server
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psql -d [database name] -U [username]
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psql -d analysis -U postgres
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-- Connecting psql to a database on a remote server
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psql -d [database name] -U [username] -h [host name]
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psql -d analysis -U postgres -h example.com
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-- Listing 18-1: Entering a single-line query in psql
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-- Enter this at the psql prompt:
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SELECT county_name FROM us_counties_pop_est_2019 ORDER BY county_name LIMIT 3;
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-- Listing 18-2: Entering a multi-line query in psql
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-- Type each line separately, followed by Enter
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SELECT county_name
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FROM us_counties_pop_est_2019
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ORDER BY county_name
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LIMIT 3;
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-- Listing 18-3: Showing open parentheses in the psql prompt
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CREATE TABLE wineries (
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id bigint,
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winery_name text
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);
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-- Listing 18-4: A query with scrolling results
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SELECT county_name FROM us_counties_pop_est_2019 ORDER BY county_name;
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-- Listings 18-5 and 18-6: Normal and expanded displays of results
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-- Use \x to toggle expanded on/off
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SELECT * FROM grades ORDER BY student_id, course_id;
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-- Listing 18-7: Importing data using \copy
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DELETE FROM state_regions;
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\copy state_regions FROM 'C:\YourDirectory\state_regions.csv' WITH (FORMAT CSV, HEADER);
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-- Listing 18-8:
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DELETE FROM state_regions;
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psql -d analysis -U postgres -c "COPY state_regions FROM STDIN WITH (FORMAT CSV, HEADER);" < state_regions.csv
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-- Listing 18-9: Saving query output to a file
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-- Enter psql settings
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\pset format csv
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-- This will be the query
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SELECT * FROM grades ORDER BY student_id, course_id;
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-- Set psql to output results
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-- Note that Windows users must supply forward slashes for
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-- this command, which is opposite of normal use.
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\o 'C:/YourDirectory/query_output.csv'
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-- Run the query and output
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SELECT * FROM grades ORDER BY student_id, course_id;
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-- ADDITIONAL COMMAND LINE UTILITIES
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-- createdb: Create a database named box_office
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createdb -U postgres -e box_office
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-- Changing user and database name
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\c [database name] [user name]
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\c box_office
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\c box_office yourname
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-- Loading shapefiles into PostgreSQL
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-- For the US Census county shapefile in Chapter 14:
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shp2pgsql -I -s 4269 -W Latin1 tl_2019_us_county.shp us_counties_2019_shp | psql -d analysis -U postgres
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-- For the Santa Fe roads and waterways shapfiles in Chapter 14:
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shp2pgsql -I -s 4269 tl_2016_35049_roads.shp santafe_roads_2016 | psql -d analysis -U postgres
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shp2pgsql -I -s 4269 tl_2016_35049_linearwater.shp santafe_linearwater_2016 | psql -d analysis -U postgres
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