运行此查询时,我在 postgres 的 SELECT 部分收到错误“列“距离”不存在”。 “距离”是指给定坐标的两点之间的距离。我怀疑这是一个时间问题?该函数在错误发生之前已正确创建。
CREATE OR REPLACE FUNCTION pg_temp.earthDistance(lat1 double precision, lng1 double precision, lat2 double precision, lng2 double precision)
RETURNS double precision AS
$BODY$
SELECT
asin(
sqrt(
sin(radians($3-$1)/2)^2 +
sin(radians($4-$2)/2)^2 *
cos(radians($1)) *
cos(radians($3))
)
) * 7918 AS distance;
$BODY$
LANGUAGE sql IMMUTABLE;
SELECT populated_place.name AS populated_place_name,
feature.name AS feature_name,
ROUND(
pg_temp.earthDistance(
populated_place.latitude,
populated_place.longitude,
feature.latitude,
feature.longitude)::NUMERIC,
2) AS distance,
RANK() OVER (PARTITION BY populated_place_name ORDER BY distance) AS rank
FROM populated_place JOIN feature ON
feature.type='summit' AND
populated_place.population>=100000
WHERE distance<=200
ORDER BY populated_place_name, rank;
最佳答案
您不能在 WHERE
子句中使用别名(distance
)。使用派生表:
SELECT
*,
RANK() OVER (PARTITION BY populated_place_name ORDER BY distance) AS rank
FROM (
SELECT
populated_place.name AS populated_place_name,
feature.name AS feature_name,
ROUND(
pg_temp.earthDistance(
populated_place.latitude,
populated_place.longitude,
feature.latitude,
feature.longitude)::NUMERIC, 2) AS distance
FROM populated_place
JOIN feature ON
feature.type='summit' AND
populated_place.population>=100000
) sub
WHERE distance <= 200
ORDER BY populated_place_name, rank;
关于postgresql - 列不存在(在查询中创建列),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/33720323/