[pgrouting-users] pgRouting: Is it possible to do multiple (concurrent) Dijkstra/A*/A_shooting_star queries at a time?

[Neutralitet]

Hello!

I have tried to post this question to gis.stackexchange.com, but there have
been no answers.

So, I have tried to post it to this mailing list:



*Disclaimer: the author of the question is a novice in PostgreSQL and
pgRouting.*

As I understand doing a shortest path query in pgRouting is a complicated
SELECT underneath.

And as I know unlike any UPDATE queries, SELECT queries in PostgreSQL can be
done simultaneously, because they don't interfere with the the database
integrity anyhow.

If the above is correct, the question is:

*Can I query pgRouting for shortest paths, for example, each 1 millisecond
and get the same timing results as in case with truly sequential shortest
path queries? Is case 2 possible?*

Usual case (1):

   - [Time elapsed: 0 seconds]
   - Query for shortest path A
   - Get result for the shortest path A
   - [Time elapsed: 1.5 seconds]
   - Query for shortest path B
   - Get result for the shortest path B
   - [Time elapsed: 3 seconds]

A case with simultaneous queries (2):

   - [Time elapsed: 0 seconds]
   - Query for shortest path A
   - [Time elapsed: 0.001 seconds]
   - Query for shortest path B
   - Get result for the shortest path A
   - [Time elapsed: 1.5 seconds]
   - Get result for the shortest path B
   - [Time elapsed: 1.5001 seconds]




--
Best regards,
Neu
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