復合SELECT查詢postgreSQL / postGIS

Question

可能有一個簡單的語法問題，但我有一個postGIS查詢，希望在單個表上運行：

SELECT 
    ST_Overlaps(g1.geom,g2.geom) AS asr_01
FROM 
    ch03.my_polygons g1, ch03.my_polygons g2
WHERE 
    g1.agent_type = 0 AND g2.agent_type != 0 AND g1.sim_time = 0.0

它可以按預期工作，但我也想選擇一個相鄰的列，例如

SELECT 
    agent_id 
FROM 
    ch03.my_polygons
WHERE 
    agent_type != 0

哪個也可以正常工作，但如何將它們結合起來？ 試過這個...

SELECT 
    agent_id,
    ST_Overlaps(g1.geom,g2.geom) AS asr_01
FROM 
    ch03.my_polygons,
    ch03.my_polygons g1, ch03.my_polygons g2 
WHERE
    agent_type != 0,
    g1.agent_type = 0 AND g2.agent_type != 0 AND g1.sim_time = 0.0

可能？ 解決這個問題的另一種方法？ 謝謝

Answer 1

好的，我通過結合使用變量來解決了...

SELECT 
    g2.agent_id,
    ST_Overlaps(g1.geom,g2.geom) AS asr_01
FROM 
    ch03.my_polygons g1, ch03.my_polygons g2 
WHERE
    g1.agent_type = 0 AND g2.agent_type != 0 AND g1.sim_time = 0.0