sql - FROM 中的子查询必须有别名 POSTGIS

Question

我正在尝试在 POSTGIS (Postgres) 数据库上使用以下查询。原题:https://gis.stackexchange.com/questions/313252/postgis-sql-query-filter-by-bounding-box

SELECT row_to_json(fc) 
FROM ( 
 SELECT 'FeatureCollection' As type, 
        array_to_json(array_agg(f)) As features 
   FROM (
     SELECT 'Feature' As type, 
     ST_AsGeoJSON(lg.geom)::json As geometry, 
     row_to_json((id, name)) As properties 
  FROM lines As lg
  WHERE lg.geom && 
      ST_SETSRID(
        ST_MakeBox2D(
            ST_MakePoint(p_BB_XLong_MIN_3857, p_BB_YLat_MIN_3857),
            ST_MakePoint(p_BB_XLong_MAX_3857, p_BB_YLat_MAX_3857)),
      3857))
) As f) As fc;

但是，我收到以下错误:

subquery in FROM must have an alias

Answer 1

您似乎没有正确计算 ( 和 )。 在 As f 之前删除 1 ) 应该没问题。