合併SQL查詢

Question

我想只用一個語句來創建這段代碼，但我需要4個不同的列。

SELECT a017tkahwin AS klaki FROM a017 WHERE a017tkahwin='K' AND a017kjantina='L' 
SELECT a017tkahwin AS blaki FROM a017 WHERE a017tkahwin='B' AND a017kjantina='L' 
SELECT a017tkahwin AS kpuan FROM a017 WHERE a017tkahwin='K' AND a017kjantina='P' 
SELECT a017tkahwin AS bpuan FROM a017 WHERE a017tkahwin='B' AND a017kjantina='P' 

Answer 1

的SQL-server2012 +使用IIF以其它方式使用CASE

SELECT 
    iif(a017tkahwin = 'K' and a017kjantina = 'L',a017tkahwin,null) AS klaki, 
    iif(a017tkahwin = 'B' and a017kjantina = 'L',a017tkahwin,null) AS blaki, 
    iif(a017tkahwin = 'K' and a017kjantina = 'P',a017tkahwin,null) AS kpuan, 
    iif(a017tkahwin = 'B' and a017kjantina = 'P',a017tkahwin,null) AS bpuan 
FROM a017 WHERE a017tkahwin IN ('K','B') AND a017kjantina in ('L','P') 

Answer 2

你能只是嘗試這樣的事：

select (SELECT a017tkahwin FROM a017 WHERE a017tkahwin='K' AND 
a017kjantina='L') as klaki , (SELECT a017tkahwin FROM a017 WHERE 
a017tkahwin='B' AND a017kjantina='L') AS blaki , (SELECT a017tkahwin FROM 
a017 WHERE a017tkahwin='K' AND a017kjantina='P') AS kpuan , (SELECT 
a017tkahwin FROM a017 WHERE a017tkahwin='B' AND a017kjantina='P') AS bpuan 

對於Oracle數據庫，您需要從雙在加結束。