SELECT
name.`field_site_sitelong_value` AS name,
basetable.`uuid`,
basetable.`nid`,
msl.`field_elevation_average_value`,
Polygon(
    coordinates.`field_geo_bounding_box_left` coordinates.`field_geo_bounding_box_bottom`,
    coordinates.`field_geo_bounding_box_right` coordinates.`field_geo_bounding_box_bottom`,
    coordinates.`field_geo_bounding_box_right` coordinates.`field_geo_bounding_box_top`,
    coordinates.`field_geo_bounding_box_left` coordinates.`field_geo_bounding_box_top`,
    coordinates.`field_geo_bounding_box_left` coordinates.`field_geo_bounding_box_bottom`
) AS geom

FROM `node` basetable
INNER JOIN `field_data_field_geo_bounding_box` coordinates
ON coordinates.`entity_id` = basetable.`nid`

INNER JOIN `field_data_field_site_sitelong` name
ON name.`entity_id` = basetable.`nid`

LEFT JOIN `field_data_field_elevation_average` msl
ON msl.`entity_id` = basetable.`nid`

WHERE basetable.`status` = 1 AND `field_geo_bounding_box_geo_type` = 'polygon'