Linq中的子查詢

Question

有人能告訴我如何將此查詢轉換爲linq？

SELECT dpr_ts 
     ,dpr_close 
     ,nvl((SELECT pay.pay_dividend 
      FROM pay 
     WHERE qot_sec_id = pay_sec_id 
       AND pay.pay_date = dpr_ts 
       AND rownum = 1),0) dividend 
    FROM dpr_mm, qot 
WHERE qot_id = dpr_qot_id 
     AND qot_id = 2027314299; 

Answer 1

var query 
= from dpr in ctx.DPR_MM 
    join qot in ctx.QOT on dpr.DPR_QOT_ID equals qot.QOT_ID 
    join pay in ctx.PAY on new { p1 = (decimal) qot.QOT_SEC_ID, p2 = dpr.DPR_TS } 
    equals new { p1 = (decimal)pay.PAY_SEC_ID , p2 = pay.PAY_DATE } 
    into ps 
    from pay in ps.DefaultIfEmpty() 
    where qot.QOT_ID == 2027314299 
    select new 
    { 
     dpr.DPR_TS, 
     dpr.DPR_CLOSE, 
     pay_dividend = pay.PAY_DIVIDEND == null ? 0 : pay.PAY_DIVIDEND 
    };