php - 将四张表合并为一张新表

Question

SELECT a.delivery_date,
       a.delivery_hour, 
       a.price as EX-ANTE, 
FROM mms_realtime_dispatch_prices_report a

  UNION ALL

SELECT b.delivery_date,
       b.delivery_hour,
       b.price as EX-POST,
FROM mms_realtime_dispatch_prices_report b

  UNION ALL

SELECT c.region,
       c.dem_rtdel,
       c.date,
FROM pub_demand_lwap c;

  UNION ALL

SELECT region,
       report,
       hour,
       SUM(q1,q2,q3,q4,q5,q6,q7,q8,q9,q10,q11)
FROM pub_markets_bids_and_offers
WHERE delivery date=03/16/2011
GROUP BY hour

救命啊!需要将这四个表合并为一个新表，无重复数据 你能帮我把这四张表合并成一张表吗？这是我第一次遇到这种情况。我真的需要帮助:(

Answer 1

在 SQL Server 中，只有当查询返回的列数量和类型相同时，联合才起作用。