ST_DFullyWithin
Name
ST_DFullyWithin — Returns true if two geometries are entirely within a given distance
Synopsis
    
     boolean
     
      ST_DFullyWithin
     
     (
    
    geometry
    
     g1
    
    , geometry
    
     g2
    
    , double precision
    
     distance
    
    
     )
    
    ;
   
Description
Returns true if the geometries are entirely within the specified distance of one another. The distance is specified in units defined by the spatial reference system of the geometries. For this function to make sense, the source geometries must both be of the same coordinate projection, having the same SRID.
       
      | 
     |
| 
       This function automatically includes a bounding box comparison that makes use of any spatial indexes that are available on the geometries.  | 
    
Availability: 1.5.0
Examples
postgis=# SELECT ST_DFullyWithin(geom_a, geom_b, 10) as DFullyWithin10, ST_DWithin(geom_a, geom_b, 10) as DWithin10, ST_DFullyWithin(geom_a, geom_b, 20) as DFullyWithin20 from
    (select ST_GeomFromText('POINT(1 1)') as geom_a,ST_GeomFromText('LINESTRING(1 5, 2 7, 1 9, 14 12)') as geom_b) t1;
-----------------
 DFullyWithin10 | DWithin10 | DFullyWithin20 |
---------------+----------+---------------+
 f             | t        | t             |