使用 Postgres/PostGIS 高效更新 200 萬行的表

Question

我有兩張桌子：

• properties （geo_point POINT、locality_id INTEGER、neighborhood_id INTEGER、id UUID）
• places_temp （id INTEGER，poly GEOMETRY，placetype TEXT）

注意： places_temp中的所有列都已編入索引。

properties有大約 200 萬行，我想：

• 使用places_temp中的id更新properties中每一行的locality_id和neighborhood_id ，其中properties.geo_point包含在places_temp.poly中的多邊形中

無論我做什么，它似乎都會掛幾個小時，在此期間我不知道它是否正常工作，連接丟失等。

關於如何高效地執行此操作的任何想法？

我的查詢：

  -- drop indexes on locality_id and neighborhood_id to speed up update
  DROP INDEX IF EXISTS idx_properties_locality_id;
  DROP INDEX IF EXISTS idx_properties_neighborhood_id;
  -- for each property find the locality and neighborhood
  UPDATE
    properties
  SET
    locality_id = (
      SELECT
        id
      FROM
        places_temp
      WHERE
        placetype = 'locality'
        -- check if geo_point is contained by polygon. geo_point is stored as SRID 26910 so must be
        -- transformed first
        AND st_intersects (st_transform (geo_point, 4326), poly)
      LIMIT 1),
  neighborhood_id = (
    SELECT
      id
    FROM
      places_temp
    WHERE
      placetype = 'neighbourhood'
      -- check if geo_point is contained by polygon. geo_point is stored as SRID 26910 so must be
      -- transformed first
      AND st_intersects (st_transform (geo_point, 4326), poly)
    LIMIT 1);
  -- Add indexes back after update
  CREATE INDEX IF NOT EXISTS idx_properties_locality_id ON properties (locality_id);
  CREATE INDEX IF NOT EXISTS idx_properties_neighborhood_id ON properties (neighborhood_id);

Answer 1

CREATE INDEX properties_point_idx ON properties USING gist (geo_point);
CREATE INDEX places_temp_poly_idx ON places_temp USING gist (poly);

UPDATE properties p
SET locality_id = x.id
FROM ( SELECT *
        , row_number() OVER () rn
        FROM places_temp t 
        WHERE t.placetype = 'locality'
        AND st_intersects (st_transform (p.geo_point, 4326), t.poly)
        )x
WHERE x.rn = 1
      ;

與其他字段類似（您可以將它們組合成一個查詢）

Answer 2

嘗試這個

        UPDATE
      properties
   SET
    locality_id =t.id, neighbourhood_id
    =t.id
    From(
    SELECT
    id
    FROM
    places_temp
  WHERE
    placetype in ('locality',  
   'neighbourhood') 
    AND st_intersects (st_transform 
   (geo_point, 4326), poly)
  LIMIT 1)) t