-
Create your points using
Point
values ofGeometry
data types inMyISAM
table. As of Mysql 5.7.5,InnoDB
tables now also supportSPATIAL
indices. -
Create a
SPATIAL
index on these points -
Use
MBRContains()
to find the values:SELECT * FROM table WHERE MBRContains(LineFromText(CONCAT( '(' , @lon + 10 / ( 111.1 / cos(RADIANS(@lat))) , ' ' , @lat + 10 / 111.1 , ',' , @lon - 10 / ( 111.1 / cos(RADIANS(@lat))) , ' ' , @lat - 10 / 111.1 , ')' ) ,mypoint)
, or, in MySQL 5.1
and above:
SELECT *
FROM table
WHERE MBRContains
(
LineString
(
Point (
@lon + 10 / ( 111.1 / COS(RADIANS(@lat))),
@lat + 10 / 111.1
),
Point (
@lon - 10 / ( 111.1 / COS(RADIANS(@lat))),
@lat - 10 / 111.1
)
),
mypoint
)
This will select all points approximately within the box (@lat +/- 10 km, @lon +/- 10km)
.
This actually is not a box, but a spherical rectangle: latitude and longitude bound segment of the sphere. This may differ from a plain rectangle on the Franz Joseph Land, but quite close to it on most inhabited places.
-
Apply additional filtering to select everything inside the circle (not the square)
-
Possibly apply additional fine filtering to account for the big circle distance (for large distances)