Returns the lineal distance between two points located on a perfect sphere of radius = 6370986m. It is more quick than geo.distanceSpheroid but less accurate.
 

1 geo.distanceSphere

<geo.distanceSphere
    ora_tol='ora_tol'
    ora_unit='M|KM|CM|MM|MILE|NAUT_MILE|FOOT|INCH|SQ_KM...'
>
    <geom1> *
        <geom1 /> *
    </geom1>
    <geom2> *
        <geom1 /> *
    </geom2>
</geo.distanceSphere>
Example
Copy
<select>
    <columns>
        <geo.distanceSphere ora_tol=''>
             <geom1>a.the_geom</geom1>
             <geom2>a.the_geom</geom2>
        </geo.distanceSphere>
    </columns>
    <from table='points' alias='a' >
        <join table='points' alias='b'>
        </join>
    </from>
    <where>
        a.name = 'Barcelona' AND b.name = 'London'
    </where>
</select>