I use postgresql 8.4 to route a river network, the following is my code typed in pgAdmin and the result is fine,
select * from driving_distance
('select gid as id,
start_id::int4 as source, end_id::int4 as target,
shape_leng::double precision as cost from network',
10, 1000000, false, false);
I have installed psycopg2 and it successfully connect python and postgresql,
#set up python and postgresql connection
import psycopg2
try:
conn = psycopg2.connect("dbname = 'routing_template' user = 'postgres' host = 'localhost' password = '****'")
except:
print 'I am unable to connect the database'
Now I need to directly execute my sql code on the top in pyscripter, how should I change these codes to python code?
I am working with postgresql 8.4, python 2.7.6 under Windows 8.1 x64.
Best Answer
First, never swallow an exception, or catch all exceptions. Your connection code should be more like:
Now, you have a connection. Running SQL is trivial ... as the psycopg2 tutorial would show you.
You can be much more sophisticated about how you output row data, etc. The manual has lots of useful examples.