这会让你接近你所需要的。我能问一下为什么不为表/列使用详细的名称吗？你只是在创造你自己的生活，下一个接手这个项目的人的生活要艰难得多。

SELECT tP.T_P,
       tP.T,
       tP.P,
       tP.Title,
       tE.EE,
       tG.CC,
       tDa.X AS A,
       tDb.X AS B,
       tDc.X AS C
FROM P AS tP
LEFT JOIN E AS tE ON tP.T_P = tE.T_P
LEFT JOIN G AS tG ON tP.T_P = tG.T_P
LEFT JOIN D AS tDa ON tP.T = tDa.T AND tP.P = tDa.P AND tDa.Type = 'A'
LEFT JOIN D AS tDb ON tP.T = tDb.T AND tP.P = tDb.P AND tDb.Type = 'B'
LEFT JOIN D AS tDc ON tP.T = tDc.T AND tP.P = tDc.P AND tDc.Type = 'C'

SELECT P.T_P,
       P.T,
       P.P,
       P.Title,
       E.EE,
       G.CC,
       MAX(CASE WHEN D.Type = 'A' THEN X END) as A,
       MAX(CASE WHEN D.Type = 'B' THEN X END) as B,
       MAX(CASE WHEN D.Type = 'C' THEN X END) as C
FROM P 
LEFT JOIN E ON P.T_P = E.T_P
LEFT JOIN G ON P.T_P = G.T_P
LEFT JOIN D ON P.T = D.T 
         AND P.P = D.P 
GROUP BY 
       P.T_P,
       P.T,
       P.P,
       P.Title,
       E.EE,
       G.CC