In Baidu Map, how does one search for N coordinates in the near distance of a database based on a coordinate point?

In Baidu Map, how to search for N coordinate points nearby in the database based on a coordinate point: some coordinate points (more than W) are stored in the existing php + mysql database, what if I used a coordinate point to obtain all the matching information within 1 km? The lng latitude field lat in the longitude field of the database .. Baidu map is used. Online, etc. thank you ., Sorting coordinate columns filter records with Euclidean distance matching conditions Baidu Map, how to search for N coordinate points in the distance near the database based on a coordinate point
Environment: php + mysql

The existing database stores some coordinate points of longitude and latitude (more than W,

What if I used a coordinate point to obtain all the matching information within 1 km?

The lng latitude field lat in the longitude field of the database ..

Baidu map is used.

Online, etc. thank you.


------ Solution --------------------
Sort coordinate column
Filter records with Euclidean distance matching conditions
------ Solution --------------------
I think:

Since the longitude and latitude of the central point are available, you can calculate the approximate longitude and latitude range of N kilometers based on the dimension .. The result is a 2N * 2N square,

For example, at 34.5 ° north latitude, there is no need to find 35 + or 34-North latitude points within 1 km. the specific conversion can be done in the program first.

However, you still need to filter some parts outside the circular radius N,

If this is the case, as long as the lng lat is combined with the index, the size of the index is 1 million and the index is very fast.