I am currently working on a geographical data processing task involving the calculation of distances between a specified geographical point and entries in an address table. The objective is to compile a list of addresses where the calculated distance falls within a predefined range.
The address table under consideration contains the following fields:
Street | City | Zip Code | Country | Lat | Lon |
---|---|---|---|---|---|
StreetName1 | CityName1 | 12345 | Country1 | 12.345678 | -45.67890 |
StreetName2 | CityName2 | 23456 | Country2 | 23.456789 | -56.78901 |
StreetName3 | CityName3 | 34567 | Country3 | 34.567890 | -67.89012 |
To perform distance calculations, I have implemented the ST_Distance_Sphere
function. In addition, I have created a database view based on this address table and executed queries against the view. Here is an illustrative example of the query:
SELECT *
FROM address_view
WHERE ST_Distance_Sphere(point(Lat, Lon), point(:given_lat, :given_lon)) < :specified_range;
However, I am facing concerns regarding the performance of this process. Calculating the distance for all records in the address table is resource-intensive. Therefore, I am seeking recommendations and strategies to optimize the efficiency of this operation. Specifically, I am interested in query optimization techniques or indexing solutions that would enhance the performance while ensuring the accurate retrieval of addresses falling within the specified distance range.
I seek guidance on efficiently using the ST_Distance_Sphere
function to calculate distances between a geographical point and addresses within a view. My goal is to retrieve addresses that meet specific distance criteria while maintaining performance standards.
Any insights on query optimization or indexing strategies are appreciated.
Fetching all the rows of the table is the performance burden.
There are several ways to take advantage of "within the specified distance range". By using a "bounding box", there are multiple solutions using INDEX, SPATIAL, or even PARTITION. See Find Nearest
If you continue with POINT
a slight improvement is to precompute the "point" for each row from the lat/lng and keep such in a separate column.