您可以比较列和值以查看两者是否为空;或两者都不为空且相等:
SELECT * FROM MYTABLE
WHERE ((A is null and :1 is null) or A = :1)
AND ((B is null and :2 is null) or B = :2)
AND ((C is null and :3 is null) or C = :3)
AND ((D is null and :4 is null) or D = :4)
AND ((E is null and :5 is null) or E = :5)
这不是很漂亮,但应该可以工作。如您所知,您不能将带有相等值的null与值进行比较,只能将is
运算符进行比较。
根据客户端软件的不同,您也许可以使用命名绑定变量来避免重复绑定。如果不是,则可以使用接受绑定的子查询或CTE,然后在主查询中使用它们。就像是:
WITH CTE AS (
SELECT :1 AS val_1, :2 AS val_2, :3 AS val_3, :4 AS val_4, :5 AS val_5
FROM DUAL
)
SELECT MT.*
FROM CTE
JOIN MYTABLE MT
ON ((MT.A is null and CTE.val_1 is null) or MT.A = CTE.val_1)
AND ((MT.B is null and CTE.val_2 is null) or MT.B = CTE.val_2)
AND ((MT.C is null and CTE.val_3 is null) or MT.C = CTE.val_3)
AND ((MT.D is null and CTE.val_4 is null) or MT.D = CTE.val_4)
AND ((MT.E is null and CTE.val_5 is null) or MT.E = CTE.val_5)
只要您确实无法拥有任何魔法值为零的列,戈登的基于函数的索引方法可能会更可靠且更易于理解。(我也错过了您的问题中的那一行,并且没有意识到您已经对此轻描淡写了!)