Provincia de Tucumán

departamentos vecinos

SELECT 
  st_x(st_transform(st_centroid(a.geom),4326)) as X, 
  st_y(st_transform(st_centroid(a.geom),4326)) as Y, 
  a.nomdep as fuente, 
  b.nomdep as destino
FROM 
  (SELECT * FROM paisxdpto2010 WHERE nomprov = 'TUCUMAN' ) as a, 
  (SELECT * FROM paisxdpto2010 WHERE nomprov = 'TUCUMAN' ) as b
WHERE st_relate(a.geom, b.geom) = 'FF2F11212';

# es equivalente a este otro query

SELECT 
  st_x(st_transform(st_centroid(a.geom),4326)) as X, 
  st_y(st_transform(st_centroid(a.geom),4326)) as Y, 
  a.nomdep as fuente, 
  b.nomdep as destino
FROM 
  (SELECT * FROM paisxdpto2010 WHERE nomprov = 'TUCUMAN' ) as a, 
  (SELECT * FROM paisxdpto2010 WHERE nomprov = 'TUCUMAN' ) as b
WHERE st_intersects(a.geom, b.geom) and not st_equals(a.geom, b.geom);