mysql - mysql 中有多个条件的情况

Question

CASE WHEN (D.BUYQ>0 AND D.SELLQ>0 AND D.series_expiry='2050-01-01') then
 sum(D.stt_INTRA_buy*least(D.buyq,D.SELLQ)*D.buyavg)+sum(D.stt_buy*(D.buyq-least(D.buyq,D.SELLQ))*D.buyavg) 
ELSE
sum(D.stt_buy*D.buyq*D.buyavg) 
 END) as xsttbuy

case 条件始终为 False，即使数据库中存在满足 True 条件的数据，它也会进入 else 状态。

Answer 1

我怀疑您的意思是将测试应用于每个数据库行，而不是每个结果行。如果是这样，您需要将案例移至总和中:

SUM(
    CASE WHEN (D.BUYQ>0 AND D.SELLQ>0 AND D.series_expiry='2050-01-01') THEN
        D.stt_INTRA_buy*LEAST(D.buyq,D.SELLQ)*D.buyavg)+D.stt_buy*(D.buyq-LEAST(D.buyq,D.SELLQ))*D.buyavg 
    ELSE
        D.stt_buy*D.buyq*D.buyavg
    END
) AS xsttbuy