32 lines
852 B
Plaintext
32 lines
852 B
Plaintext
create schema v;
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-- create the roads table
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create table v.roads (
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id serial primary key,
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source integer,
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target integer,
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cost double precision
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);
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-- insert sample data into roads table
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insert into v.roads (source, target, cost) values
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(1, 2, 1.0),
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(2, 3, 1.0),
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(3, 4, 1.0),
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(1, 3, 2.5),
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(3, 5, 2.0);
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-- create a function to use pgRouting to find the shortest path
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select * from pgr_dijkstra(
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'select id, source, target, cost from v.roads',
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1, -- start node
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4 -- end node
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);
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seq | path_seq | node | edge | cost | agg_cost
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-----+----------+------+------+------+----------
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1 | 1 | 1 | 1 | 1 | 0
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2 | 2 | 2 | 2 | 1 | 1
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3 | 3 | 3 | 3 | 1 | 2
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4 | 4 | 4 | -1 | 0 | 3
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(4 rows)
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drop schema v cascade;
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NOTICE: drop cascades to table v.roads
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